Ectopic CRH/ACTH-Co-Secreting Neuroendocrine Tumors Leading to Cushing’s Disease

Posted on March 17, 2025 by MaryO

Abstract

Adrenocorticotropic hormone (ACTH) and corticotropin-releasing hormone (CRH) are essential regulators of cortisol production within the hypothalamic-pituitary-adrenal (HPA) axis. Elevated cortisol levels, resulting from excessive ACTH, can lead to Cushing’s syndrome, a condition with significant morbidity. Neuroendocrine tumors (NETs) can ectopically produce both ACTH and CRH, contributing to this syndrome. This review discusses the pathophysiology, types, clinical presentation, diagnosis, and management of these tumors. Emphasis is placed on the importance of identifying dual CRH/ACTH secretion, which complicates diagnosis and necessitates tailored therapeutic strategies. Furthermore, the review highlights the prognosis, common complications, and future directions for research in this area.

We report the case of a 53-year-old female patient who presented with severe Cushing’s syndrome and was diagnosed with ectopic ACTH syndrome. Despite initial indications pointing towards pituitary-dependent hypercortisolism, further investigations revealed the presence of a highly differentiated atypically located tumor in the upper lobe of the left lung, adjacent to the mediastinum. Immunohistochemistry of the tumor tissue demonstrated not only ACTH but also CRH and CRH-R1 expression. The simultaneous expression of these molecules supports the hypothesis of the presence of a positive endocrine feedback loop within the NET, in which the release of CRH stimulates the expression of ACTH via binding to CRH-R1. This case report highlights the challenges in diagnosing and managing ectopic ACTH syndrome, emphasizing the importance of a comprehensive diagnostic approach to identify secondary factors impacting cortisol production, such as CRH production and other contributing neuroendocrine mechanisms.

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Ectopic Adrenocorticotrophic Hormone Syndrome in a 10-Year-Old Girl With a Thymic Neuroendocrine Tumor

Posted on November 29, 2024 by MaryO

Abstract

Background

Thymic neuroendocrine tumor as a cause of Cushing syndrome is extremely rare in children.

Case presentation

We report a case of a 10-year-old girl who presented with typical symptoms and signs of hypercortisolemia, including bone fractures, growth retardation, and kidney stones. The patient was managed with oral ketoconazole, during which she experienced adrenal insufficiency, possibly due to either cyclic adrenocorticotropic hormone (ACTH) secretion or concurrent COVID-19 infection. The patient underwent a diagnostic work-up which indicated the possibility of an ACTH-secreting pituitary neuroendocrine tumor. However, after a transsphenoidal surgery, the diagnosis was not confirmed on histopathological examination. Subsequent bilateral inferior petrosal sinus sampling showed strong indications of the presence of ectopic ACTH syndrome. Detailed rereading of functional imaging studies, including 18F-FDG PET/MRI and 68Ga DOTATOC PET/CT, ultimately identified a small lesion in the thymus. The patient underwent videothoracoscopic thymectomy that confirmed a neuroendocrine tumor with ACTH positivity on histopathological examination.

Conclusion

This case presents some unique challenges related to the diagnosis, management, and treatment of thymic neuroendocrine tumor in a child. We can conclude that ketoconazole treatment was effective in managing hypercortisolemia in our patient. Further, a combination of functional imaging studies can be a useful tool in locating the source of ectopic ACTH secretion. Lastly, in cases of discrepancy in the results of stimulation tests, bilateral inferior petrosal sinus sampling is highly recommended to differentiate between Cushing disease and ectopic ACTH syndrome.

Peer Review reports

Background

In children above seven years of age, the majority of pediatric Cushing syndrome (CS) cases are caused by a pituitary neuroendocrine tumors (PitNET). However, a differential diagnosis of hypercortisolemia in children is often challenging concerning the interpretation of stimulation tests and the fact that up to 50% of PitNET may not be detected on magnetic resonance imaging (MRI) [1]. An ectopic adrenocorticotropic hormone (ACTH) syndrome (EAS) is extremely rare in children. Its diagnosis is often missed or confused with Cushing disease (CD) [2]. Most ACTH-secreting tumors originate from bronchial or thymic neuroendocrine tumors (NETs), or less commonly, from NETs in other locations. To diagnose EAS, specific functional imaging studies are often indicated to elucidate the source of ACTH production.

Pharmacotherapy may be used before surgery to control hypercortisolemia and its symptoms/signs, or in patients in whom the source of hypercortisolism has not been found (e.g., EAS), or surgery failed. Ketoconazole or metyrapone, as adrenal steroidogenesis blockers, were found to be very efficient, although they exhibit side effects [3].

Furthermore, cyclic secretion of ACTH followed by fluctuating plasma cortisol levels is extremely rare in children, including those with EAS [4, 5]. Therefore, in cyclic EAS, the use of steroid inhibitors or acute illness or trauma can be associated with adrenal insufficiency, which can be life-threatening. Here we describe the clinical features, laboratory and radiological investigations, results, management, and clinical outcome of a 10-year-old girl with a thymic NET presenting with ACTH secretion.

Case presentation

A 10-year-old girl was acutely admitted to our university hospital for evaluation of facial edema and macroscopic hematuria in May 2021. A day before admission, she presented to the emergency room for dysuria, pollakiuria, nausea, and pain in her right lower back. Over the past year she had experienced excessive weight gain with increased appetite and growth retardation (Fig. 1). Her height over three years had shifted from the 34th to the 13th centile (Fig. 1). Her parents noticed facial changes, pubic hair development, increased irritability, and moodiness.

Fig. 1

figure 1

Body weight, body height, and body mass index development of the case patient. The black arrow indicates the first presentation, the blue arrow indicates the start of ketoconazole treatment and the yellow arrow indicates the time of thymectomy. Mid-parental height is indicated by the green line

At admission, she was found to have a moon face with a plethora, few acne spots on forehead, as well as facial puffiness. In contrast to slim extremities, an abnormal fat accumulation was observed in the abdomen. Purple striae were present on abdomen and thighs. She did not present with any bruising, proximal myopathy, or edema. On physical examination, she was prepubertal, height was 135 cm (13th centile), and weight was 37 kg (69th centile) with a BMI of 20.4 kg/m2 (90th centile). She developed persistent hypertension. Her past medical history was uneventful except for two fractures of her upper left extremity after minimal trips one and three years ago, both treated with a caste. Apart from hypothyroidism on the maternal side, there was no history of endocrine abnormalities or tumors in the family.

In the emergency room, the patient was started on sulfonamide, pain medication, and intravenous (IV) fluids. Her hypertensive crises were treated orally with angiotensin-converting enzyme inhibitor or with a combination of adrenergic antagonists and serotonin agonists administered IV. Hypokalemia had initially been treated with IV infusion and then with oral potassium supplements. A low serum phosphate concentration required IV management. The initial investigation carried out in the emergency room found hematuria with trace proteinuria. Kidney ultrasound showed a 5 mm stone in her right ureter with a 20 mm hydronephrosis. She did not pass any kidney stones, however, fine white sand urine analysis reported 100% brushite stone.

Hypercortisolemia was confirmed by repeatedly increased 24-hour urinary free cortisol (UFC), (5011.9 nmol/day, normal range 79.0-590.0 nmol/day). Her midnight cortisol levels were elevated (961 nmol/l, normal range 68.2–537 nmol/l). There was no suppression of serum cortisol after 1 mg overnight dexamethasone suppression test (DST) or after low-dose DST (LDDST). An increased morning plasma ACTH (30.9 pmol/l, normal range 1.6–13.9 pmol/) suggested ACTH-dependent hypercortisolemia. There was no evidence of a PitNET on a 1T contrast-enhanced MRI. The high-dose DST (HDDST) did not induce cortisol suppression (cortisol 1112 nmol/l at 23:00, cortisol 1338 nmol/l at 8:00). Apart from the kidney stone, a contrast-enhanced computed tomography (CT) of her neck, chest, and abdomen/pelvis did not detect any lesion. Various tumor markers were negative and the concentration of chromogranin A was also normal.

A corticotropin-releasing hormone (CRH) stimulation test induced an increase in serum cortisol by 32% at 30 min and ACTH concentration by 67% at 15 min (Table 1). A 3T contrast-enhanced MRI scan of the brain identified a 3 × 2 mm lesion in the lateral right side of the pituitary gland (Fig. 2). An investigation of other pituitary hormones was unremarkable. Apart from low serum potassium (minimal level of 2.8 mmol/l; normal range 3.3–4.7 mmol/l) and phosphate (0.94 mmol/l; normal range 1.28–1.82 mmol/l) concentrations, electrolytes were normal. The bone mineral density assessed by whole dual-energy X-ray absorptiometry was normal.

Fig. 2

figure 2

Coronal and sagittal 3T contrast-enhanced brain MRI scans. A suspected 3 × 2 mm lesion in the lateral right side of the pituitary gland (yellow arrows)

The patient was presented at the multidisciplinary tumor board and it was decided that she undergoes transsphenoidal surgery for the pituitary lesion. No PitNET was detected on histopathological examination and no favorable biochemical changes were noted after surgery. After the patient recovered from surgery, subsequent bilateral inferior petrosal sinus sampling (BIPSS) confirmed EAS as the maximum ratio of central to peripheral ACTH concentrations was only 1.7. During the investigation for tumor localization, she was started on ketoconazole treatment (300 mg/day) to alleviate symptoms and signs of hypercortisolism. Treatment with ketoconazole had a beneficial effect on patient health (Fig. 1). There was a weight loss of 2 kg in a month, a disappearance of facial plethora, and a decrease in vigorous appetite. Her liver function tests remained within the normal range.

Table 1 Result of corticotropin-releasing hormone stimulation test

The 24-hour UFC excretion normalized three weeks after ketoconazole initiation. However, six weeks after continuing ketoconazole therapy (400 mg/day), the patient complained of nausea, vomiting, and diarrhea. She was found to have adrenal insufficiency with a low morning serum cortisol of 10.70 nmol/l (normal range 68.2–537 nmol/l) and salivary cortisol concentrations < 1.5 nmol/l (normal range 1.7–29 nmol/l). She was also found to be positive for COVID-19 infection. Ketoconazole treatment was stopped and our patient was educated to take stress steroids in case of persisting or worsening symptoms. Her clinical status gradually improved and steroids were not required.

Meanwhile, whole-body fluorine-18 fluorodeoxyglucose positron emission tomography (18F-FDG PET)/MRI was performed with no obvious hypermetabolic lesion suspicious of a tumor. No obvious accumulation was detected on 68Ga-DOTATOC PET/CT images (Fig. 3). However, a subsequent careful and detailed re-review of the images detected a discrete lesion on 18F-FDG PET/MRI and 68Ga-DOTATOC PET/CT scans in the left anterior mediastinum, in the thymus (Fig. 4).

Fig. 3

figure 3

18F-FDG PET/MRI (A) and 68Ga-DOTATOC (B) PET/CT scans. Whole body MIP reconstructions. Subtle correspondent focal hyperactivity in the left mediastinum (black arrow). The 18F-FDG PET/MRI image courtesy of Prof. Jiri Ferda, MD, PhD, Clinic of the Imaging Methods, University Hospital Plzen, Czech Republic

Fig. 4

figure 4

Axial slices of PET/MRI (A–C) and 68Ga-DOTATOC (D–F) PET/CT scans. Subtle correspondent focal hyperactivity in the left mediastinum (white arrow). No obvious finding on MRI (C) and CT (F) scans. The FDG PET/MRI image courtesy of Prof. Jiri Ferda, MD, PhD, Clinic of the Imaging Methods, University Hospital Plzen, Czech Republic

Three weeks after the episode of adrenal insufficiency and being off ketoconazole treatment, our patient´s pre-surgery laboratory tests showed slightly low morning cortisol 132 nmol/l with surprisingly normal ACTH 2.96 pmol/l (normal range 1.6–13.9 pmol/). Given the upcoming surgery, she was initiated on a maintenance dose of hydrocortisone (15 mg daily = 12.5 mg/m2/day). Further improvement of cushingoid characteristics (improvement of facial plethora and moon face, weight loss) was noticed. Our patient underwent videothoracoscopic surgery, and a hyperplastic thymus of 80 × 70 × 15 mm with a 4 mm nodule was successfully removed. Tumor immunohistochemistry was positive for ACTH, chromogranin A, CD56, and synaptophysin. Histopathological findings were consistent with a well-differentiated NET grade 1. A subsequent genetic screening did not detect any pathogenic variant in the MEN1 gene.

After surgery, hydrocortisone was switched to a stress dose and gradually decreased to a maintenance dose. Antihypertensive medication was stopped and further weight loss was observed after thymectomy. Within a few weeks after the thoracic surgery, the patient entered puberty, her mood improved significantly, and potassium supplements were stopped. Finally, hydrocortisone treatment was stopped ten months after thymectomy.

Discussion and conclusions

The case presented here demonstrates a particularly challenging work-up of the pediatric patient with the diagnosis of CS caused by EAS due to thymic NET. Differentiating CD and EAS can sometimes be difficult, including the use of various laboratory and stimulation tests and their interpretation, as well as proper, often challenging, reading of functional imaging modalities, especially if a discrete lesion is present at an unusual location [1]. When using established criteria for Cushing disease (for the CRH test an increase of cortisol and/or ACTH by ≥ 20% or ≥ 35%, respectively, and a ≥ 50% suppression of cortisol for the HDDST) our patient presented discordant results. The CRH stimulation test induced an increase in cortisol by 32% and ACTH by 67% and the 3T MRI pointed to the right-side pituitary lesion, both to yield false positive results. The HDDST, on the other hand, did not induce cortisol suppression and was against characteristic findings for CD. We did not proceed with desmopressin testing, which also induces an excess ACTH and cortisol response in CD patients and has rarely been used in pediatric patients, except in those with extremely difficult venous access [6]. Recently published articles investigated the reliability of CRH stimulation tests and HDDST and both concluded that the CRH test has greater specificity than HDDST [7, 8]. Elenius et al. suggested optimal response criteria as a ≥ 40% increase of ACTH and/or cortisol (cortisol as the most specific measure of CD) during the CRH test and a ≥ 69% suppression of serum cortisol during HDDST [7]. Using these criteria, the CD would be excluded in our patient. To demonstrate that the proposed thresholds for the test interpretation widely differ, Detomas et al. proposed a ≥ 12% cortisol increase and ≥ 31% ACTH increase during the CRH test to confirm CD [8].

The fact that up to 50% of PitNET may not be detected on MRI [1] and that more than 20% of patients with EAS are reported to have pituitary incidentalomas [9] makes MRI somewhat unreliable in differentiating CD and EAS. However, finally, well-established and generally reliable BIPSS in our patient supported the diagnosis of EAS. Thus, BIPSS is considered a gold standard to differentiate between CD and EAS; however, it can still provide false negative results in cyclic CS if performed in the trough phase [10] or in vascular anomalies or false positive results as in a recent case of orbital EAS [11].

In children, the presence of thymus tissue may be misinterpreted as normal. Among other reports of thymic NET [12], Hanson et al. reported a case of a prepubertal boy in whom a small thymic NET was initially treated as normal thymus tissue on CT [13]. In our case, initially, the lesion was not detected on the 18F-FDG and 68Ga-DOTATOC PET scans. A small thymic NET was visible only after a detailed and careful re-reading of both PET scans. Although somatostatin receptor (SSR) PET imaging may be helpful in identifying ectopic CRH- or ACTH-producing tumors, there are still some limitations [13]. For example, in the study by Wannachalee et al., 68Ga-DOTATATE identified suspected primary lesions causing ECS in 65% of patients with previously occult tumors and was therefore concluded as a sensitive method for primary as well as metastatic tumors [14]. In our patient, the final correct diagnosis was based on the results of both PET scans. This is in full support of the article published by Liu et al. who concluded that 18F-FDG and SSR PET scans are complementary in determining the proper localization of ectopic ACTH production [15]. Additionally, it is worth noting that not all NETs stain positively for ACTH which may present a burden in its identification.

To control hypercortisolemia, both ketoconazole and metyrapone were considered in our patient. Due to the side effects of metyrapone on blood pressure, ketoconazole was started as a preferred option in our pediatric patient. A retrospective multicenter study concluded that ketoconazole treatment is effective with acceptable side effects, with no fatal hepatitis and adrenal insufficiency in 5.4% of patients [3]. During ketoconazole treatment, our patient developed adrenal insufficiency; however, it is impossible to conclude whether this was solely due to ketoconazole treatment or whether an ongoing COVID-19 infection contributed to the adrenal insufficiency or whether this was caused by a phase of lower or no ACTH secretion from the tumor often seen in patients with cyclic ACTH secretion. The patient’s cyclic ACTH secretion is highly probable since her morning cortisol was slightly lower and ACTH was normal, even after being off ketoconazole treatment for 3 weeks.

When retrospectively and carefully reviewing all approaches to the diagnostic and management care of our pediatric patient, it would be essential to proceed to BIPSS before any pituitary surgery, especially when obtaining discrepant results from stimulation tests, as well as detecting a discrete pituitary lesion (≤ 6 mm) as recommended by the current guidelines [16]. This was our first experience using ketoconazole in a young child, and although this treatment was associated with very good outcomes in treating hypercortisolemia, close monitoring, and family education on signs and symptoms of adrenal insufficiency are essential to recognizing adrenal insufficiency promptly in any patient with EAS, especially those presenting also with some other comorbidities or stress, here COVID-19 infection.

In conclusion, the pediatric patient here presenting with EAS caused by thymic NET needs very careful assessment including whether cyclic CS is present, the outline of a good management plan to use all tests appropriately and in the correct sequence, monitoring carefully for any signs or symptoms of adrenal insufficiency, and apply appropriate imaging studies, with experienced radiologists providing accurate readings. Furthermore, ketoconazole treatment was found to be effective in reducing the symptoms and signs of CS in this pediatric patient. Finally, due to the rarity of this disease and the challenging work-up, we suggest that a multidisciplinary team of experienced physicians in CS management is highly recommended.

Data availability

No datasets were generated or analysed during the current study.

Abbreviations

ACTH:
Adrenocorticotrophic hormone
BIPSS:
Bilateral inferior petrosal sinus sampling
CD:
Cushing disease
CRH:
Corticotropin-releasing hormone
CS:
Cushing syndrome
CT:
Computed tomography
DST:
Dexamethasone suppression test
EAS:
Ectopic adrenocorticotropic hormone syndrome
18F-FDG PET:
Fluorine-18 fluorodeoxyglucose positron emission tomography
HDDST:
High-dose dexamethasone suppression test
IV:
Intravenous
LDDST:
Low-dose dexamethasone suppression test
NET:
Neuroendocrine tumor
PitNET:
Pituitary neuroendocrine tumor
UFC:
Urinary free cortisol

References

  1. Streuli R. A rare case of an ACTH/CRH co-secreting midgut neuroendocrine tumor mimicking Cushing’s disease. Endocrinol Diabetes Metab Case Rep. 2017;2017:17–58. ,Krull I, Brändle M, et al.

    PubMed PubMed Central Google Scholar

  2. Karageorgiadis AS, Papadakis GZ, Biro J, et al. Ectopic adrenocorticotropic hormone and corticotropin-releasing hormone co-secreting tumors in children and adolescents causing cushing syndrome: a diagnostic dilemma and how to solve it. J Clin Endocrinol Metab. 2015;100(1):141–8.

    Article CAS PubMed Google Scholar

  3. Castinetti F, Guignat L, Giraud P, et al. Ketoconazole in Cushing’s disease: is it worth a try? J Clin Endocrinol Metab. 2014;99(5):1623–30.

    Article CAS PubMed Google Scholar

  4. Mi Q, Yin M-Z, Gao Y-J et al. Thymic atypical carcinoid with cyclical Cushing’s syndrome in a 7-year-old boy: a case report and review of the literature. Intern Med. 2014;4(5).

  5. Moszczyńska E, Pasternak-Pietrzak K, Prokop-Piotrkowska M, et al. Ectopic ACTH production by thymic and appendiceal neuroendocrine tumors – two case reports. J Pediatr Endocrinol Metab. 2020;34(1):141–6.

    Article PubMed Google Scholar

  6. Crock PA, Ludecke DK, Knappe UJ, et al. A personal series of 100 children operated for Cushing’s disease (CD): optimizing minimally invasive diagnosis and transnasal surgery to achieve nearly 100% remission including reoperations. J Pediatr Endocrinol Metab. 2018;31(9):1023–31.

    Article CAS PubMed Google Scholar

  7. Elenius H, McGlotten R, Nieman LK. Ovine CRH stimulation and 8 mg dexamethasone suppression tests in 323 patients with ACTH-dependent Cushing’s syndrome. J Clin Endocrinol Metab. 2023;109(1):e189–189.

    Article Google Scholar

  8. Detomas M, Ritzel K, Nasi-Kordhishti I, et al. Outcome of CRH stimulation test and overnight 8 mg dexamethasone suppression test in 469 patients with ACTH-dependent Cushing’s syndrome. Front Endocrinol (Lausanne). 2022;13:955945.

    Article PubMed Google Scholar

  9. Yogi-Morren D, Habra MA, Faiman C, et al. Pituitary MRI findings in patients with pituitary and ectopic ACTH-dependent Cushing syndrome: does a 6-mm pituitary tumor size cut-off value exclude ectopic ACTH syndrome? Endocr Pract. 2015;21(10):1098–103.

    Article PubMed Google Scholar

  10. Albani A, Berr CM, Beuschlein F, et al. A pitfall of bilateral inferior petrosal sinus sampling in cyclic Cushing’s syndrome. BMC Endocr Disord. 2019;19(1):105.

    Article PubMed PubMed Central Google Scholar

  11. Tan H, Chen D, Yu Y, et al. Unusual ectopic ACTH syndrome in a patient with orbital neuroendocrine tumor, resulted false-positive outcome of BIPSS: a case report. BMC Endocr Disord. 2020;20(1):116.

    Article CAS PubMed PubMed Central Google Scholar

  12. Ahmed MF, Ahmed S, Abdussalam A, et al. A rare case of ectopic adrenocorticotropic hormone syndrome (EAS) in an adolescent girl with a thymic neuroendocrine tumour. Cureus. 2024;16(8):e66615.

    PubMed PubMed Central Google Scholar

  13. Hanson JA, Sohaib SA, Newell-Price J, et al. Computed tomography appearance of the thymus and anterior mediastinum in active Cushing’s syndrome. J Clin Endocrinol Metab. 1999;84:602–5.

    CAS PubMed Google Scholar

  14. Wannachalee T, Turcu AF, Bancos I, et al. The clinical impact of [68 Ga]-DOTATATE PET/CT for the diagnosis and management of ectopic adrenocorticotropic hormone – secreting Tumours. Clin Endocrinol (Oxf). 2019;91(2):288–94.

    Article PubMed Google Scholar

  15. Liu Q, Zang J, Yang Y, et al. Head-to-head comparison of 68Ga-DOTATATE PET/CT and 18F-FDG PET/CT in localizing tumors with ectopic adrenocorticotropic hormone secretion: a prospective study. Eur J Nucl Med Mol Imaging. 2021;48(13):4386–95.

    Article CAS PubMed Google Scholar

  16. Flesiriu M, Auchus R, Bancos I, et al. Consensus on diagnosis and management of Cushing’s disease: a guideline update. Lancet Diabetes Endocrinol. 2021;9(12):847–75.

    Article Google Scholar

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Acknowledgements

The authors thank all the colleagues from the Thomayer University Hospital and Military University Hospital who were involved in the inpatient care of this patient.

Funding

This work was supported by the Charles University research program Cooperatio Pediatrics, Charles University, Third Faculty of Medicine, Prague.

Author information

Authors and Affiliations

  1. Department of Children and Adolescents, Third Faculty of Medicine, Charles University, University Hospital Kralovske Vinohrady, Šrobárova 50, Prague, 100 34, Czech Republic

    Irena Aldhoon-Hainerová

  2. Department of Pediatrics, Thomayer University Hospital, Prague, Czech Republic

    Irena Aldhoon-Hainerová

  3. Department of Medicine, Military University Hospital, Prague, Czech Republic

    Mikuláš Kosák

  4. Third Department of Medicine, First Faculty of Medicine, Charles University, Prague, Czech Republic

    Michal Kršek

  5. Institute of Nuclear Medicine, First Faculty of Medicine, Charles University, General University Hospital, Prague, Czech Republic

    David Zogala

  6. Developmental Endocrinology, Metabolism, Genetics and Endocrine Oncology Affinity Group, Eunice Kennedy Shriver NICHD, NIH, Bethesda, MD, USA

    Karel Pacak

Contributions

All authors made individual contributions to the authorship. IAH, MK, MK, and DZ were involved in the diagnosis and management of this patient. DZ was responsible for the patient´s imaging studies. IAH wrote the first draft of the manuscript. KP revised the manuscript critically. All authors reviewed and approved the final draft.

Corresponding author

Correspondence to Irena Aldhoon-Hainerová.

Ethics declarations

Ethics approval and consent to participate

Not applicable.

Consent for publication

Signed informed consent was obtained from the patient and the patient´s parents for the publication of this case report and accompanying images.

Competing interests

The authors declare no competing interests.

Additional information

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https://bmcendocrdisord.biomedcentral.com/articles/10.1186/s12902-024-01756-5

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Olfactory Neuroblastoma Causing Cushing’s Syndrome Due to the Ectopic Adrenocorticotropic Hormone (ACTH) Secretion

Posted on March 27, 2024 by MaryO

Abstract

Cushing’s syndrome is a constellation of features occurring due to high blood cortisol levels. We report a case of a 47-year-old male with a history of recurrent olfactory neuroblastoma (ONB). He presented with bilateral lower limb weakness and anosmia and was found to have Cushing’s syndrome due to high adrenocorticotropic hormone (ACTH) levels from an ectopic source, ONB in this case. Serum cortisol and ACTH levels declined after tumor removal.

Introduction

Olfactory neuroblastoma (ONB), or esthesioneuroblastoma, is a rare malignancy arising from neuroepithelium in the upper nasal cavity. It represents approximately 2% of all nasal passage tumors, with an incidence of approximately 0.4 per 2.5 million individuals [1]. ONB shares similar histological features with small round blue cell neoplasms of the nose. Ectopic hormone secretion is a very rare feature associated with these tumors. Five-year overall survival is reported to be between 60% and 80% [2,3]. The age distribution is either in the fifth to sixth decade of life [4,5], or in the second and sixth decades [6].

Features of Cushing’s syndrome (moon face, buffalo hump, central obesity hypertension, fragile skin, easy bruising, fatigue, muscle weakness) are due to high blood cortisol levels [7]. It can be either primary (cortisol-secreting adrenal tumor), secondary (adrenocorticotropic hormone (ACTH)-secreting pituitary tumor, also called Cushing disease), or ectopic ACTH secretion (from a non-pituitary source). All three types share similar features [8].

Ectopic ACTH syndrome (EAS) is due to an extra pituitary tumor, producing ACTH. It accounts for 12-17% of Cushing’s syndrome cases [9]. Most cases of EAS-producing tumors are in the lungs, mediastinum, neuroendocrine tumors of the gastrointestinal tract, and pheochromocytomas [9]. Ectopic ACTH secretion from an ONB is very rare. As of 2015, only 18 cases were reported in the literature [10]. Here, we report such a case.

Case Presentation

Our patient is a 47-year-old Bangladeshi male, with a history of recurrent ONB that was resected twice in the past (transsphenoidal resection in 2016 and 2019) with adjuvant radiotherapy, no chemotherapy was given. He also had diabetes mellitus type 1 (poorly controlled) and hypertension. He presented with bilateral lower limb weakness, anosmia, decreased oral intake, loss of taste for one week, and bilateral submandibular swelling that increased in size gradually over the past two years. There was no history of fever, cough, abdominal pain, or exposure to sick contacts. The patient reported past episodes of similar symptoms, but details are unclear. The patient’s family history is positive for diabetes mellitus type 1 in both parents. Lab tests in the emergency department showed hypokalemia and hyperglycemia as detailed in Table 1. He was admitted for further workup of the above complaints.

Test Patient Results Reference Range Unit Status
Hemoglobin 14.7 13-17 g/dL Normal
White blood cell (WBC) 17.9 4-10 10*9/L High
Neutrophils 15.89 2-7 10*9/L High
Lymphocytes 1.07 1-3 10*9/L Normal
Sodium 141 136-145 mmol/L Normal
Potassium 2.49 3.5-5.1 mmol/L Low (Panic)
Chloride 95 98-107 mmol/L Low
Glucose 6.52 4.11-5.89 mmol/L Elevated
C-reactive protein (CRP) 0.64 Less than 5 mg/L Normal
Erythrocyte sedimentation rate (ESR) 2 0-30 mm/h Normal
Creatinine 73 62-106 µmol/L Normal
Uric acid 197 202.3-416.5 µmol/L Normal
Alanine aminotransferase (ALT) 33.2 0-41 U/L Normal
Aspartate aminotransferase (AST) 18.6 0-40 U/L Normal
International Normalised Ratio (INR) 1.21 0.8-1.2 sec High
Prothrombin time (PT) 15.7 12.3-14.7 sec High
Lactate dehydrogenase (LDH) 491 135-225 U/L High
Thyroid-stimulating hormone (TSH) 0.222 0.27-4.20 mIU/L Low
Adrenocorticotropic hormone (ACTH) 106 ≤50 ng/L Elevated
Cortisol (after dexamethasone suppression) 1750 Morning hours (6-10 am): 172-497 nmol, Afternoon hours (4-8 pm): 74.1-286 nmol nmol/L Elevated (failure of suppression)
24-hour urine cortisol (after dexamethasone suppression) 5959.1 <120 nmol/24 hrs nmol/24hr Elevated (failure of suppression)
Table 1: Results of blood test at the time of hospitalization. Hypokalemia and high values of adrenocorticotropic hormone and cortisol were confirmed.

On examination, the patient’s vital signs were as follows: blood pressure was 154/77 mmHg, heart rate of 60 beats per minute, respiratory rate was 18 breaths per minute, oxygen saturation of 98% on room air, and a temperature of 36.7°C. The patient had a typical Cushingoid appearance with a moon face, buffalo hump, purple striae on the abdomen, central obesity, and hyperpigmentation of the skin. Submandibular lymph nodes were enlarged bilaterally. The examination of the submandibular lymph nodes showed a firm, fixed mass extending from the angle of the mandible to the submental space on the left side. Neurological examination showed weakness in both legs bilaterally (strength 3/5) and anosmia (checked by orthonasal smell test). The rest of the neurological exam was normal.

Laboratory findings revealed (in Table 1) a marked hypokalemia of 2.49 mmol/L and hyperglycemia of 6.52 mmol/L. The serum cortisol level was elevated at 1587 nmol/L. Serum ACTH levels were raised at 106 ng/L (normal value ≤50 ng/L). Moreover, the high-dose dexamethasone suppression test failed to lower the serum ACTH levels and serum and urine cortisol. Serum cortisol level after the suppression test was 1750 nmol/L, while 24-hour urine cortisol after the test was 5959.1 nmol/24hr. Serum ACTH levels after the test also remained high at 100mg/L. This indicated failure of ACTH suppression by high-dose dexamethasone, which points towards ectopic ACTH production. Other blood tests (complete blood count, liver function tests) were insignificant.

A computed tomography scan with contrast (CT scan) of the chest, abdomen, and pelvis, with a special focus on the adrenals, was negative for any malignancy or masses. CT scan of the neck showed bilaterally enlarged submandibular lymph nodes and an enlarged right lobe of the thyroid with nodules. Fine needle aspiration (FNA) of the thyroid nodules revealed a benign nature. Magnetic resonance imaging (MRI) of the brain showed a contrast-enhancing soft tissue lesion (18x18x10mm) in the midline olfactory groove area with extension into the frontal dura and superior sagittal sinus, suggesting recurrence of the previous ONB. There was evidence of previous surgery also. The pituitary gland was normal (Figures 1–2).

A-brain-MRI-(T1-weighted;-without-contrast;-sagittal-plane)-shows-a-soft-tissue-lesion-located-in-the-midline-olfactory-groove-area.-Dural-surface-with-extension-into-anterior-frontal-dura.
Figure 1: A brain MRI (T1-weighted; without contrast; sagittal plane) shows a soft tissue lesion located in the midline olfactory groove area. Dural surface with extension into anterior frontal dura.

MRI: Magnetic resonance imaging

A-brain-MRI-(T2-weighted;-without-contrast;-axial-plane)-shows-a-soft-tissue-lesion-located-in-the-midline-olfactory-groove-area.
Figure 2: A brain MRI (T2-weighted; without contrast; axial plane) shows a soft tissue lesion located in the midline olfactory groove area.

MRI: Magnetic resonance imaging

Octreotide scintigraphy showed three focal abnormal uptakes in the submandibular cervical nodes. Additionally, there was a moderate abnormal uptake at the midline olfactory groove with bilateral extension (Figure 3).

Whole-body-octreotide-scan-(15-mCi-99mTc-Octreotide-IV)-demonstrates-three-focal-abnormal-uptakes:-the-largest-(5.2-x-2.4-cm)-in-the-left-submandibular-region,-and-two-smaller-ones-on-the-right,-suggestive-of-lymph-node-uptake.-Additional-abnormal-uptake-was-seen-along-the-midline-of-the-olfactory-groove-region-with-bilateral-extension.-No-other-significant-abnormal-uptake-was-identified.
Figure 3: Whole-body octreotide scan (15 mCi 99mTc-Octreotide IV) demonstrates three focal abnormal uptakes: the largest (5.2 x 2.4 cm) in the left submandibular region, and two smaller ones on the right, suggestive of lymph node uptake. Additional abnormal uptake was seen along the midline of the olfactory groove region with bilateral extension. No other significant abnormal uptake was identified.

On microscopic examination, an excisional biopsy after the transcranial resection surgery of the frontal skull base tumor showed nests and lobules of round to oval cells with clear cytoplasm, separated by vascular and hyalinized fibrous stroma (Figures 4A–4B). Tumor cells show mild to moderate nuclear pleomorphism, and fine chromatin (Figure 4C). A fibrillary neural matrix is also present. Some mitotic figures can be seen. Immunohistochemical stains revealed positive staining for synaptophysin (Figure 4D) and chromogranin (Figure 4E). Stains for CK (AE1/AE3), CD45, Desmin, and Myogenin are negative. Immunostaining for ACTH was focally positive (Figure 4F), while the specimen of the cervical lymph nodes showed the same staining, indicating metastases. The cytomorphologic and immunophenotypic features observed are consistent with a Hyams grade II ONB, with ectopic ACTH production.

Histopathological-and-immunohistochemical-findings-of-olfactory-neuroblastoma.
Figure 4: Histopathological and immunohistochemical findings of olfactory neuroblastoma.

A (100x magnification) and B (200x magnification) – hematoxylin and eosin (H-E) staining shows cellular nests of round blue cells separated by hyalinized stroma. C (400x magnification) – nuclei show mild to moderate pleomorphism with fine chromatin. D (100x magnification) – an immunohistochemical stain for synaptophysin shows diffuse, strong cytoplasmic positivity within tumor cells. E (200x magnification) – tumor cells are positive for chromogranin. F (400x magnification) – ACTH cytoplasmic expression in tumor cells.

ACTH: adrenocorticotropic hormone

For his resistant hypokalemia, he had to be given intravenous (IV) and oral potassium chloride (KCL) repeatedly. The patient underwent transcranial resection of the frontal skull base tumor. The patient received cefazolin for seven days, and hydrocortisone for four days. After transcranial resection, his cortisol level decreased to 700 nmol/L. Furthermore, ACTH dropped, and serum potassium also normalized. Subsequently, the patient was transferred to the intensive care unit (ICU) for meticulous monitoring and continued care. In the ICU, the patient developed one episode of a generalized tonic-clonic seizure, which aborted spontaneously, and the patient received phenytoin and levetiracetam to prevent other episodes. A right-sided internal jugular vein and left transverse sinus thrombosis were also developed and treated with enoxaparin sodium. Following surgery, his low potassium levels improved, resulting in an improvement in his limb weakness. His other symptoms also gradually improved after surgery. Three weeks following the primary tumor resection, he underwent bilateral neck dissection with right hemithyroidectomy, for removal of the metastases. The patient opted out of chemotherapy and planned for an international transfer to his home country for further management. Other treatments that he received during hospitalization were ceftriaxone, azithromycin, and Augmentin®. Insulin was used to manage his diabetes, perindopril to regulate his blood pressure, and spironolactone to increase potassium retention. Omeprazole was administered to prevent GI bleeding and heartburn/gastroesophageal reflux disease relief after discharge.

Discussion

ONB was first described in 1924, and it is a rare neuroectodermal tumor that accounts for 2% of tumors affecting the nasal cavity [11]. Even though ONB has a good survival rate, long-term follow-up is necessary due to the disease’s high recurrence rate [2]. ONB recurrence has been approximated to range between 30% and 60% after successful treatment of the primary tumor [12]. Recurrent disease is usually locoregional and tends to have a long interval to relapse with a mean of six years [12]. The first reported case of ectopic ACTH syndrome caused by ONB was in 1987 by M Reznik et al., who reported a 48-year-old woman with ONB who developed a Cushing-like syndrome 28 months before her death [13].

The occurrence of Cushing’s syndrome due to ectopic ACTH can occur either in the initial tumor or even years later during its course or after recurrence [3,6,9,14]. Similar to the case of Abe et al. [3], our patient also presented with muscle weakness due to hypokalemia, which is a feature of Cushing’s syndrome. Hypokalemia is present at diagnosis in 64% to 86% of cases of EAS and is resistant to treatment [9,14], as seen in our case. In our patient, the exact time of development of Cushing’s syndrome could not be ascertained due to the non-availability of previous records. However, according to the patient, he started developing abdominal obesity, pigmentation, and buffalo hump in 2021 about two years after his second surgery for ONB.

The distinction between pituitary ACTH and ectopic ACTH involves utilizing CT/MRI of the pituitary, corticotropin-releasing hormone (CRH) stimulation test with petrosal sinus blood sampling, high dose dexamethasone suppression test, and checking serum K+ (more commonly low in ectopic ACTH) [2,15,16]. In our case, a CRH stimulation test was not available but CT/MRI brain, dexamethasone test, low serum potassium, plus the postoperative fall in cortisol levels, all pointed towards an ectopic ACTH source.

Conclusions

In conclusion, this case highlights the rare association between ONB and ectopic ACTH syndrome, which developed after tumor recurrence. The patient’s unique presentation of bilateral lower limb weakness and hypokalemia can cause diagnostic challenges, emphasizing the need for comprehensive diagnostic measures. Surgical intervention proved crucial, with postoperative cortisol values becoming normal, highlighting the efficacy of this approach. The occurrence of ectopic ACTH production in ONB patients, although very rare, is emphasized, so that healthcare professionals who deal with these tumors are aware of this complication. This report contributes valuable insights shedding light on the unique ONB manifestation causing ectopic ACTH syndrome. The ongoing monitoring of the patient’s clinical features will further enrich the understanding of the course of this uncommon phenomenon in the medical literature.

References

  1. Thompson LD: Olfactory neuroblastoma. Head Neck Pathol. 2009, 3:252-9. 10.1007/s12105-009-0125-2
  2. Abdelmeguid AS: Olfactory neuroblastoma. Curr Oncol Rep. 2018, 20:7. 10.1007/s11912-018-0661-6
  3. Abe H, Suwanai H, Kambara N, et al.: A rare case of ectopic adrenocorticotropic hormone syndrome with recurrent olfactory neuroblastoma. Intern Med. 2021, 60:105-9. 10.2169/internalmedicine.2897-19
  4. Yin Z, Wang Y, Wu Y, et al.: Age distribution and age-related outcomes of olfactory neuroblastoma: a population-based analysis. Cancer Manag Res. 2018, 10:1359-64. 10.2147/CMAR.S151945
  5. Platek ME, Merzianu M, Mashtare TL, Popat SR, Rigual NR, Warren GW, Singh AK: Improved survival following surgery and radiation therapy for olfactory neuroblastoma: analysis of the SEER database. Radiat Oncol. 2011, 6:41. 10.1186/1748-717X-6-41
  6. Elkon D, Hightower SI, Lim ML, Cantrell RW, Constable WC: Esthesioneuroblastoma. Cancer. 1979, 44:3-1087. 10.1002/1097-0142(197909)44:3<1087::aid-cncr2820440343>3.0.co;2-a
  7. Nieman LK, Biller BM, Findling JW, Newell-Price J, Savage MO, Stewart PM, Montori VM: The diagnosis of Cushing’s syndrome: an Endocrine Society Clinical Practice Guideline. J Clin Endocrinol Metab. 2008, 93:1526-40. 10.1210/jc.2008-0125
  8. Chabre O: Cushing syndrome: physiopathology, etiology and principles of therapy [Article in French]. Presse Med. 2014, 43:376-92. 10.1016/j.lpm.2014.02.001
  9. Isidori AM, Lenzi A: Ectopic ACTH syndrome. Arq Bras Endocrinol Metabol. 2007, 51:1217-25. 10.1590/s0004-27302007000800007
  10. Kunc M, Gabrych A, Czapiewski P, Sworczak K: Paraneoplastic syndromes in olfactory neuroblastoma. Contemp Oncol (Pozn). 2015, 19:6-16. 10.5114/wo.2015.46283
  11. Finlay JB, Abi Hachem R, Jang DW, Osazuwa-Peters N, Goldstein BJ: Deconstructing olfactory epithelium developmental pathways in olfactory neuroblastoma. Cancer Res Commun. 2023, 3:980-90. 10.1158/2767-9764.CRC-23-0013
  12. Ni G, Pinheiro-Neto CD, Iyoha E, et al.: Recurrent esthesioneuroblastoma: long-term outcomes of salvage therapy. Cancers (Basel). 2023, 15:1506. 10.3390/cancers15051506
  13. Reznik M, Melon J, Lambricht M, Kaschten B, Beckers A: Neuroendocrine tumor of the nasal cavity (esthesioneuroblastoma). Apropos of a case with paraneoplastic Cushing’s syndrome [Article in French]. Ann Pathol. 1987, 7:137-42.
  14. Kadoya M, Kurajoh M, Miyoshi A, et al.: Ectopic adrenocorticotropic hormone syndrome associated with olfactory neuroblastoma: acquirement of adrenocorticotropic hormone expression during disease course as shown by serial immunohistochemistry examinations. J Int Med Res. 2018, 46:4760-8. 10.1177/0300060517754026
  15. Clotman K, Twickler MTB, Dirinck E, et al.: An endocrine picture in disguise: a progressive olfactory neuroblastoma complicated with ectopic Cushing syndrome. AACE Clin Case Rep. 2017, 3:278-83. 10.4158/EP161729.CR
  16. Chung YS, Na M, Ku CR, Kim SH, Kim EH: Adrenocorticotropic hormone-secreting esthesioneuroblastoma with ectopic Cushing’s syndrome. Yonsei Med J. 2020, 61:257-61. 10.3349/ymj.2020.61.3.257

From https://www.cureus.com/articles/226080-olfactory-neuroblastoma-causing-cushings-syndrome-due-to-the-ectopic-adrenocorticotropic-hormone-acth-secretion-a-case-report?score_article=true#!/

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Cushing’s Syndrome caused by ACTH Precursors Secreted from a Pancreatic Yolk Sac Tumor in an Adult

Posted on January 8, 2024 by MaryO

Here, we report the first adult case of pancreatic yolk sac tumor with ectopic adrenocorticotropic hormone (ACTH) syndrome. The patient was a 27-year-old woman presenting with abdominal distension, Cushingoid features, and hyperpigmentation. Endogenous Cushing’s syndrome was biochemically confirmed. The ACTH level was in the normal range, which raised the suspicion of ACTH precursor-dependent disease. Elevated ACTH precursors were detected, supporting the diagnosis of ectopic ACTH syndrome. Functional imaging followed by tissue sampling revealed a pancreatic yolk sac tumor. The final diagnosis was Cushing’s syndrome due to a yolk sac tumor. The patient received a steroidogenesis inhibitor and subsequent bilateral adrenalectomy for control of hypercortisolism. Her yolk sac tumor was treated with chemotherapy and targeted therapy. Cushing’s syndrome secondary to a yolk sac tumor is extremely rare. This case illustrated the utility of ACTH precursor measurement in confirming an ACTH-related pathology and distinguishing an ectopic from a pituitary source for Cushing’s syndrome.

Introduction

Ectopic adrenocorticotrophic hormone (ACTH) syndrome, also termed paraneoplastic Cushing’s syndrome, can be caused by the secretion of ACTH and/or ACTH precursors from ectopic tumors. The tumors concerned secrete ACTH precursors, including unprocessed proopiomelanocortin (POMC) and POMC-derived peptides, owing to the altered post-translational processing of POMC (1). These tumors are associated with intense hypercortisolism and various complications, such as hypertension, hyperglycemia, osteoporosis, infection risks, and thrombotic tendencies (2). Distinguishing ectopic from pituitary-dependent Cushing’s syndrome is often challenging. The two conditions are classically distinguished by their variable responses to dynamic endocrine tests, including the high-dose dexamethasone suppression test, the corticotrophin-releasing-factor (CRF) test, and the desmopressin test (3). Pituitary imaging may sometimes provide a diagnosis if a pituitary macroadenoma is identified at this juncture. The gold standard for diagnosing pituitary Cushing’s is a positive inferior petrosal sinus sampling (IPSS) result. The measurement of ACTH precursors is reported to have diagnostic value in this scenario (4).

The most common source of ectopic ACTH is intrathoracic tumors, including bronchial carcinoid and small cell lung cancers. Other possible sources include gut neuroendocrine tumors and medullary thyroid cancer. Recognizing the potential causes of ectopic ACTH syndrome is essential as this provides guidance in locating the causative tumor and allows tumor-directed therapies. A yolk sac tumor as a cause of ectopic ACTH syndrome has only been reported in a 2-year-old child but not in adults (5). Here, we present a case of a 27-year-old Chinese woman who had Cushing’s syndrome due to ectopic ACTH precursor production from a pancreatic yolk sac tumor.

Case description

A 27-year-old Chinese woman, who had unremarkable past health and family history, presented with right upper quadrant abdominal pain and nausea in early 2020. Abdominal ultrasonography was unrevealing. A few months later, she developed Cushingoid features and oligomenorrhea. At presentation, her blood pressure was 160/95 mmHg, body weight was 65.6 kg, and body mass index was 23.2 kg/m2. She had a moon face, hirsutism, proximal myopathy, bruising, thinning of the skin, and acne. She also had hyperpigmentation on the nails and knuckles of both hands (Figure 1).

Figure 1
www.frontiersin.orgFigure 1. Cushingoid features at presentation include moon face, acne, thin skin, and easy bruising. Hyperpigmentation on the nails and knuckles was also noted.

Diagnostic assessments

Her 9 am and 9 pm cortisol were both >1,700 nmol/L. Her 24-h urine-free cortisol was beyond the upper measurable limit at >1,500 nmol/L. Her serum cortisol was 759 nmol/L after a 1 mg overnight-dexamethasone suppression test, confirming endogenous Cushing’s syndrome. The morning ACTH was 35 pg/mL (upper limit of normal is 46 pg/mL). After excluding a high dose-hook effect, her blood sample was concomitantly sent for ACTH measurement using two different platforms to eliminate possible interference, which might cause a falsely low ACTH reading. ACTH was 19 pg/mL (upper limit of normal is 46 pg/mL) using an IMMULITE 2000 XPI, Siemens Healthineers, Erlangen, Germany, and 17 pg/mL (reference range: 7–63 pg/mL) using a Cobas e-801, Roche Diagnostics, Indianapolis, IN, United States, therefore verifying the ACTH measurement.

In view of this being ACTH-dependent Cushing’s syndrome, a high-dose-dexamethasone suppression test (HDDST) was performed, and her cortisol was not suppressed at 890 nmol/L, with ACTH 42 pg/mL. The serum cortisol day profile showed a mean cortisol level of >1,700 nmol/L (i.e., higher than the upper measurable limit of the assay) and an ACTH of 17 pg/mL. A CRF test using 100 μg of corticorelin showed less than a 50% rise in ACTH and no rise in cortisol levels (Supplementary Table S1). She suffered from multiple complications of hypercortisolism, including thoracic vertebral collapse with back pain, diabetes mellitus (HbA1c 6.7% and fasting glucose 7.6 mmol/L), and hypokalemic hypertension, with a lowest potassium level of 2.3 mmol/L.

The rapid onset of intense hypercortisolism and refractory hypokalemia, as well as the responses in the HDDST and CRF tests raised the suspicion of ectopic ACTH syndrome. Tumor markers were measured. Alpha-fetoprotein (AFP) was markedly raised at 33,357 ng/mL (reference range: <9 ng/mL). Beta-human chorionic gonadotropin (beta-hCG) was not elevated. Carcinoembryonic antigen (CEA) was 4.0 ng/mL (reference range: <3 ng/mL) and CA 19–9 was 57 U/mL (reference range: <37 U/mL). The marked hyperpigmentation in the context of normal ACTH levels pointed to the presence of an underlying tumor producing circulating ACTH precursors. Hence, magnetic resonance imaging (MRI) of the pituitary gland was not performed at this juncture. ACTH precursors were measured using a specialized immunoenzymatic assay (IEMA) employing in-house monoclonal antibodies against the ACTH region and the gamma MSH region. Both monoclonal antibodies have to bind to these regions in POMC and pro-ACTH to create a signal. The patient had a level of 4,855 pmol/L (upper limit of normal is 40 pmol/L) (6). This supported Cushing’s syndrome from an ectopic source secondary to an excess in ACTH precursors.

Localization studies were arranged to identify the source of ectopic ACTH precursors. Computed tomography (CT) of the thorax did not show any significant intrathoracic lesion but incidentally revealed a pancreatic mass. Dedicated CT of the abdomen confirmed the presence of a 7.9 × 5.6 cm lobulated mass in the pancreatic body; the adrenal glands were unremarkable. 18-FDG and 68Ga-DOTATATE dual-tracer positron-emission tomography-computed tomography (PET-CT) showed that the pancreatic mass was moderately FDG-avid and non-avid for DOTATATE (Supplementary Figure S1). Multiple FDG-avid nodal metastases were also present, including left supraclavicular fossa lymph nodes.

Fine needle aspiration of the left supraclavicular fossa lymph node yielded tumor cells featuring occasional conspicuous nucleoli, granular coarse chromatin, irregular nuclei, and a high nuclear-to-cytoplasmic ratio. Mitotic figures were infrequent. On immunostaining, the tumor cells were positive for cytokeratin 7 and negative for cytokeratin 20. Focal expression of CDX-2, chromogranin, and synaptophysin was noted. They were negative for TTF-1, GCDPF, Gata 3, Pax-8, CD56, ACTH, inhibin, and S-100 protein. Further immunostaining was performed in view of highly elevated AFP. The tumor cells expressed AFP, Sall4, and MNF-116. They were negative for c-kit, calretinin, Melan A and SF-1. Placental ALP (PLAP) was weak and equivocal. The features were in keeping with a yolk sac tumor.

Therapeutic intervention and outcome

The patient had significant hypokalemic hypertension requiring losartan 100 mg daily, spironolactone 100 mg daily, and a potassium supplement of 129 mmol/day. Co-trimoxazole was given for prophylaxis against Pneumocystis jirovecii pneumonia. Metyrapone was started and up-titrated to 1 gram three times per day. However, in view of persistent hypercortisolism, with urinary free cortisol persistently above the upper measurable limit of the assay, bilateral adrenalectomy was performed. The tumor was mainly in the periadrenal soft tissue, with vascular invasion. The tumor formed cords, nests, and ill-defined lumen (Figure 2). The tumor cells were polygonal and contained pale to eosinophilic cytoplasm and pleomorphic nuclei, some with large nucleoli. Mitosis was present while tumor necrosis was not obvious. The stroma was composed of vascular fibrous tissue, with minimal inflammatory reaction. Immunohistochemical study showed that the tumor was positive for cytokeratin 7, MNF-116, AFP, and glypican-3, and also positive for Sall4 and HNF1β. The tumor cells were negative for cytokeratin 20, PLAP, CD30, negative for neuroendocrine markers including S100 protein, synaptophysin, chromogranin, and also negative for Melan-A, inhibin, and ACTH. Histochemical study for Periodic acid–Schiff–diastase (PAS/D) showed no cytoplasmic zymogen granules like those of acinar cell tumor. The features were compatible with yolk sac tumor. She was put on glucocorticoid and mineralocorticoid replacements post-operatively.

Figure 2
www.frontiersin.orgFigure 2. Histology and immunohistochemical staining pattern of tumor specimen. (A) HE stain x 40 showing tumor cells in the soft tissue and peritoneum. (B) HE × 400 showing that the tumor forms cords, nests, and ill-formed lumen in the vascular stroma. The tumor cells are polygonal with pale cytoplasm and pleomorphic nuclei. (C) PAS/D stain showing no cytoplasmic zymogen granules. (D) Tumor is diffusely positive for cytokeratin 7. (E) Tumor is positive for AFP. (F) Tumor is positive for glypican-3. (G) Tumor is diffusely positive for HNF1β. (H) Tumor is diffusely positive for SALL4.

Regarding her oncological management, she received multiple lines of chemotherapy, but the response was poor. Due to limited access to the ACTH precursor assay, serial measurement was unavailable. Treatment response was monitored by repeated imaging and monitoring of AFP. Figure 3 shows a timeline indicating the key events of the disease, showing the trends of the AFP and cortisol levels. Apart from (i) bleomycin, etoposide, and platinum, she was sequentially treated with (ii) etoposide, ifosfamide with cisplatin, and (iii) palliative gemcitabine with oxaliplatin. Next-generation sequencing showed a BRAF V600E mutation, for which (iv) dabrafenib and trametinib were given. Unfortunately, the disease progressed, and the patient succumbed approximately one year after the disease was diagnosed.

Figure 3
www.frontiersin.orgFigure 3. Timeline with serial cortisol and alpha-fetoprotein levels from diagnosis to patient death.

Discussion

This case demonstrates the diagnostic value of ACTH precursor measurement in the diagnosis of ectopic Cushing’s syndrome. ACTH precursors are raised in all ectopic tumors responsible for Cushing’s syndrome and could be useful in distinguishing ectopic from pituitary Cushing’s syndrome (4). Moreover, Cushing’s syndrome due to a yolk sac tumor has been reported only once in a pediatric case, and this is the first adult case reported in the literature (5).

POMC is sequentially cleaved in the anterior pituitary into pro-ACTH and then into ACTH, which is released into the circulation and binds to ACTH receptors in the adrenal cortex, leading to glucocorticoid synthesis (5, 7). Due to incomplete processing, ACTH precursors are found in normal subjects at a concentration of 5–40 pmol/L (6). Pituitary tumors are traditionally well-differentiated and can also relatively efficiently process ACTH precursors. However, this processing is less efficient in ectopic tumors that cause Cushing’s syndrome (8). Some less differentiated pituitary macroadenomas can secrete ACTH precursors into the circulation; however, these tumors are diagnosed by imaging and so do not, in general, cause problems with differential diagnosis (9).

Measurement of ACTH precursors by immunoradiometric assay (IRMA) was first described by Crosby et al. (10). The assay utilized monoclonal antibodies specific for ACTH and the other binding gamma-MSH. The assay only detects peptides expressing both epitopes and therefore measures POMC and pro-ACTH. The assay does not cross-react with other POMC-derived peptides such as beta-lipotropin, ACTH, and N-POMC.

Oliver et al. demonstrated that, compared to the pituitary adenomas in Cushing’s disease, all ectopic tumors responsible for Cushing’s syndrome in their study produce excessive POMC and pro-ACTH (4). The excessive production of ACTH precursors may reflect neoplasm-induced modification and amplification of POMC production. It is suggested that POMC binds to and activates the ACTH receptor because it contains the ACTH amino-acid sequence, or it is cleaved to ACTH in the adrenal glands to cause hypercortisolism (5) (Figure 4). Moreover, cleavage of POMC may produce peptides that exert mitogenic actions on adrenal cells and lead to adrenocortical growth. Outside the adrenal tissue, excessive ACTH precursors in Cushing’s syndrome caused by ectopic tumors can lead to marked hyperpigmentation. Both hypercortisolism and hyperpigmentation were observed in the reported case.

Figure 4
www.frontiersin.orgFigure 4. Postulated pathological mechanism of ectopic ACTH precursors.

In patients with ACTH-dependent Cushing’s syndrome, ectopic tumors should be distinguished from pituitary tumors. The HDDST, at a cut-off of 50% cortisol suppression, gives a sensitivity of 81% and a specificity of 67% for pituitary dependent Cushing’s syndrome (11). The CRF test provides 82% sensitivity and 75% specificity for pituitary disease (8). IPSS is the gold standard in distinguishing pituitary from ectopic tumors in Cushing’s syndrome. Utilization of CRF-stimulated IPSS provides 93% sensitivity and 100% specificity for pituitary disease. It also allows correct lateralization in 78% of patients with pituitary tumors. However, it is only available in specialized centers.

In a retrospective cohort, the ACTH precursor level distinguished well between Cushing’s disease and ectopic ACTH syndrome (4). With a cut-off of 100 pmol/L, the test achieved 100% sensitivity and specificity for ectopic ACTH syndrome. More recently, this assay has been used to diagnose patients with occult ectopic ACTH syndrome, with ACTH precursors above 36 pmol/L (8). Unfortunately, the immunoassay for ACTH precursor measurement utilizes in-house monoclonal antibodies, which are not widely available.

Cross-reactivity of POMC in commercially available ACTH assays ranges from 1.6% to 4.7% (12). In cases of ectopic tumors causing Cushing’s syndrome with markedly raised ACTH-precursors and intense hypercortisolism, the cross-reactivity would give significantly high ‘ACTH’ measurements to suggest an ACTH-related pathology. The degree of cross-reactivity, which is variable, should ideally be provided by the assay manufacturer as it affects result interpretation. Lower levels of ACTH precursor production might not be detected, especially by assays with low precursor cross-reactivity. Clinical vigilance is crucial in reaching the correct diagnosis. In patients with marked hypercortisolism and a normal ACTH concentration, like in this case, the measurement of ACTH precursors would allow the accurate diagnosis of Cushing’s syndrome caused by ACTH precursors.

Ectopic tumors causing Cushing’s syndrome are associated with more intense hypercortisolism than Cushing’s disease (11). However, due to variable cross-reactivity, commercial ACTH assays might not accurately detect the excessive ACTH precursors responsible for the clinical syndrome. For this reason, ACTH measurements in these two conditions can significantly overlap and may not differentiate between ectopic and pituitary diseases (4). On the other hand, the more specific POMC assay described in 1996, which does not cross-react with pro-ACTH, has a low sensitivity of 80% for ectopic Cushing’s syndrome and is not now available (13). Hence, the ACTH precursor assay used in this reported case, which detects POMC and pro-ACTH, appears to provide the best diagnostic accuracy from the available literature.

Serial measurement of ACTH precursors may play a role in monitoring the treatment response in an ACTH precursor secreting tumor. In the case of ectopic ACTH secretion, the corticotropic axis is slowed down and ACTH is almost exclusively of paraneoplastic origin. Immunotherapy is known to alter the functioning of the hypothalamic–pituitary corticotropic axis; however, its effect on ectopic secretions is not known. More data is required before the role of ACTH precursor measurement for disease monitoring in these scenarios can be ascertained.

The incidence of endogenous Cushing’s syndrome is reported to be 2 to 4 per million people per year (14). Ectopic sources of Cushing’s syndrome are responsible for 9 to 18% of these cases. Typical sources of these ectopic tumors include bronchial carcinoid tumors, small-cell lung cancer, and gut neuroendocrine tumors. Notably, germ cell tumors, including teratomas, ovarian epithelial tumors, and ovarian endometrial tumors, are also possible ectopic sources of Cushing’s syndrome.

The histological diagnosis of germ cell tumor in a non-genital site is challenging, especially for the poorly differentiated, or with somatic differentiation. Immunostaining, chromosomal, or genetic study are very important in confirming the diagnosis. AFP elevation in our case limited the differential diagnoses to germ cell tumors/yolk sac tumors, hepatocellular carcinoma, and rare pancreatic tumors. The specimen was biopsied from the retroperitoneum, and the morphology was a dominant trabecular pattern or a hepatoid pattern. It showed diffuse positive immunostaining for cytokeratin, AFP, and glypican-3. It was also diffusely and strongly positive for HNF1β and SALL4, supporting the diagnosis of yolk sac tumor. Both HNF1β and SALL4, being related with the expression of genes associated with stem cells or progenitor cells, are used as sensitive and specific markers for germ cell tumors/yolk sac tumors (15, 16).

Staining related to pancreatic acinar cell carcinoma and neuroendocrine tumor were performed. PAS/D staining showed a lack of zymogen granules. A lack of nuclear β-catenin positivity was shown. Staining for neuroendocrine markers, including chromogranin and synaptophysin, was negative. Bcl-10 and trypsin were not available in the local setting.

Cushing’s syndrome due to a yolk sac tumor was reported only once, in a 2-year-old child (5). The abdominal yolk sac tumor was resistant to cisplatin, with rapid disease progression, and the patient succumbed 1.5 years after initial presentation. Yolk sac tumor in the pancreas is also rare, with only 4 cases reported so far. The first case was reported in a 57-year-old woman with an incidentally detected abdominal mass (17). The tumor stained positive for AFP, PLAP, and CEA. The second case was a 70-year-old asymptomatic woman with histology showing a group of tumor cells with features of a yolk sac tumor, and another group showing features of pancreatic ductal adenocarcinoma with mucin production, suggesting a yolk sac tumor derived from pancreatic ductal adenocarcinoma (18). The tumor showed partial positivity for AFP, Sall4, glypican-3, and cytokeratin 7, as found in our case, while MNF-116 and PLAP staining results were not described. The third was in a 33-year-old man with a solitary pancreatic head mass with obstructive jaundice (19). The patient had undergone Whipple’s procedure followed by cisplatin-based chemotherapy, resulting in at least 5 years of disease remission. The latest reported case was in a 32-year-old man presenting with abdominal pain (20). Notably, initial imaging showed diffuse enlargement of the pancreas and increased FDG uptake without a distinct mass. Reassessment imaging 11 months later showed a 13 cm pancreatic mass. The initial imaging findings suggested initial intraductal growth of the tumor, as reported in some subtypes of pancreatic carcinoma. None of the reported cases of adult pancreatic yolk sac tumors were associated with abnormal hormone secretion. We reported the first adult case of pancreatic yolk sac tumor with ectopic ACTH syndrome. The case represents an overlap of two rarities. It demonstrates that pancreatic yolk sac tumor is a possible cause of ectopic ACTH syndrome.

Conclusion

ACTH precursor measurement helps to distinguish ectopic ACTH syndrome from Cushing’s disease. The test has superior diagnostic performance and is less invasive than IPSS. Nonetheless, the limited availability of the assay may restrict its broader use in patient management. We describe the first adult case of pancreatic yolk sac tumor with ACTH precursor secretion resulting in Cushing’s syndrome. This adds to the list of origins of ectopic ACTH syndrome in adults.

Data availability statement

The original contributions presented in the study are included in the article/Supplementary material, further inquiries can be directed to the corresponding author.

Ethics statement

Written informed consent was obtained from the individual to publish any potentially identifiable images or data in this article.

Author contributions

JC wrote the manuscript. JC, CW, WC, AW, KW, and PT researched the data. WC, AL, EL, YW, KT, KL, and CL critically reviewed and edited the manuscript. DL initiated and conceptualized this case report and is the guarantor of this work. All authors contributed to the article and approved the submitted version.

Funding

The author(s) declare that no financial support was received for the research, authorship, and/or publication of this article.

Conflict of interest

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Publisher’s note

All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.

Supplementary material

The Supplementary material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fmed.2023.1246796/full#supplementary-material

References

1. Stewar, PM, Gibson, S, Crosby, SR, Pennt, R, Holder, R, Ferry, D, et al. ACTH precursors characterize the ectopic ACTH syndrome. Clin Endocrinol. (1994) 40:199–204. doi: 10.1111/j.1365-2265.1994.tb02468.x

PubMed Abstract | CrossRef Full Text | Google Scholar

2. Young, J, Haissaguerre, M, Viera-Pinto, O, Chabre, O, Baudin, E, and Tabarin, A. MANAGEMENT OF ENDOCRINE DISEASE: Cushing’s syndrome due to ectopic ACTH secretion: an expert operational opinion. Eur J Endocrinol. (2020) 182:R29–58. doi: 10.1530/EJE-19-0877

PubMed Abstract | CrossRef Full Text | Google Scholar

3. Fleseriu, M, Auchus, R, Bancos, I, Ben-Shlomo, A, Bertherat, J, Biermasz, NR, et al. Consensus on diagnosis and management of Cushing’s disease: a guideline update. Lancet Diabetes Endocrinol. (2021) 9:847–75. doi: 10.1016/S2213-8587(21)00235-7

PubMed Abstract | CrossRef Full Text | Google Scholar

4. Oliver, RL, Davis, JR, and White, A. Characterisation of ACTH related peptides in ectopic Cushing’s syndrome. Pituitary. (2003) 6:119–26. doi: 10.1023/B:PITU.0000011172.26649.df

PubMed Abstract | CrossRef Full Text | Google Scholar

5. Gevers, EF, Meredith, S, Shah, P, Torpiano, J, Peters, C, Sebire, NJ, et al. Cushing syndrome in a child due to pro-opiomelanocortin (POMC) secretion from a yolk sac tumor. Eur J Endocrinol. (2017) 176:K1–7. doi: 10.1530/EJE-16-0776

PubMed Abstract | CrossRef Full Text | Google Scholar

6. Gibson, S, Crosby, SR, Stewart, MF, Jennings, AM, McCall, E, and White, A. Differential release of proopiomelanocortin-derived peptides from the human pituitary: evidence from a panel of two-site immunoradiometric assays. J Clin Endocrinol Metab. (1994) 78:835–41.

PubMed Abstract | Google Scholar

7. Harno, E, Gali Ramamoorthy, T, Coll, AP, and White, A. POMC: the physiological power of hormone processing. Physiol Rev. (2018) 98:2381–430. doi: 10.1152/physrev.00024.2017

CrossRef Full Text | Google Scholar

8. Page-Wilson, G, Freda, PU, Jacobs, TP, Khandji, AG, Bruce, JN, Foo, ST, et al. Clinical utility of plasma POMC and AgRP measurements in the differential diagnosis of ACTH-dependent Cushing’s syndrome. J Clin Endocrinol Metab. (2014) 99:E1838–45. doi: 10.1210/jc.2014-1448

PubMed Abstract | CrossRef Full Text | Google Scholar

9. Gibson, S, Ray, DW, Crosby, SR, Dornan, TL, Jennings, AM, Bevan, JS, et al. Impaired processing of proopiomelanocortin in corticotroph macroadenomas. J Clin Endocrinol Metab. (1996) 81:497–502.

PubMed Abstract | Google Scholar

10. Crosby, SR, Stewart, MF, Ratcliffe, JG, and White, A. Direct measurement of the precursors of adrenocorticotropin in human plasma by two-site immunoradiometric assay. J Clin Endocrinol Metab. (1988) 67:1272–7. doi: 10.1210/jcem-67-6-1272

PubMed Abstract | CrossRef Full Text | Google Scholar

11. Aron, DC, Raff, H, and Findling, JW. Effectiveness versus efficacy: the limited value in clinical practice of high dose dexamethasone suppression testing in the differential diagnosis of adrenocorticotropin-dependent Cushing’s syndrome. J Clin Endocrinol Metab. (1997) 82:1780–5. doi: 10.1210/jc.82.6.1780

PubMed Abstract | CrossRef Full Text | Google Scholar

12. Monaghan, PJ, Kyriacou, A, Sturgeon, C, Davies, A, Trainer, PJ, White, A, et al. Proopiomelanocortin interference in the measurement of adrenocorticotrophic hormone: a United Kingdom National External Quality Assessment Service study. Clin Endocrinol. (2016) 85:569–74. doi: 10.1111/cen.13118

CrossRef Full Text | Google Scholar

13. Raffin-Sanson, ML, Massias, JF, Dumont, C, Raux-Demay, MC, Proeschel, MF, Luton, JP, et al. High plasma proopiomelanocortin in aggressive adrenocorticotropin-secreting tumors. J Clin Endocrinol Metab. (1996) 81:4272–7.

PubMed Abstract | Google Scholar

14. Beuschlein, F, and Hammer, GD. Ectopic pro-opiomelanocortin syndrome. Endocrinol Metab Clin N Am. (2002) 31:191–234. doi: 10.1016/S0889-8529(01)00025-1

CrossRef Full Text | Google Scholar

15. Yu, DD, Guo, SW, Jing, YY, Dong, YL, and Wei, LX. A review on hepatocyte nuclear factor-1beta and tumor. Cell Biosci. (2015) 5:58. doi: 10.1186/s13578-015-0049-3

PubMed Abstract | CrossRef Full Text | Google Scholar

16. Miettinen, M, Wang, Z, McCue, PA, Sarlomo-Rikala, M, Rys, J, Biernat, W, et al. SALL4 expression in germ cell and non-germ cell tumors: a systematic immunohistochemical study of 3215 cases. Am J Surg Pathol. (2014) 38:410–20. doi: 10.1097/PAS.0000000000000116

PubMed Abstract | CrossRef Full Text | Google Scholar

17. Zhang, B, Gao, S, Chen, Y, and Wu, Y. Primary yolk sac tumor arising in the pancreas with hepatic metastasis: a case report. Korean J Radiol. (2010) 11:472–5. doi: 10.3348/kjr.2010.11.4.472

PubMed Abstract | CrossRef Full Text | Google Scholar

18. Yonemaru, J, Takahashi, M, Nara, S, Ichikawa, H, Ishigamori, R, Imai, T, et al. A yolk sac tumor of the pancreas and derived xenograft model effectively responded to VIP chemotherapy. Pancreatology. (2020) 20:551–7. doi: 10.1016/j.pan.2019.12.021

PubMed Abstract | CrossRef Full Text | Google Scholar

19. Galanis, I, Floros, G, Simou, M, Kyriakopoulos, G, and Stylianidis, G. An extremely rare case of a primary pancreatic yolk sac tumor. Cureus. (2022) 14:e26007. doi: 10.7759/cureus.26007

PubMed Abstract | CrossRef Full Text | Google Scholar

20. Sui, H, Zhu, Z, Li, Z, and Luo, Y. Primary pancreatic yolk sac tumor presenting as diffusely enlarged pancreas in initial 18F-FDG PET/CT. Clin Nucl Med. (2020) 45:483–6. doi: 10.1097/RLU.0000000000003038

PubMed Abstract | CrossRef Full Text | Google Scholar

Keywords: Cushing’s syndrome, ectopic ACTH syndrome, yolk sac tumor, pancreatic tumor, ACTH precursor

Citation: Chang JYC, Woo CSL, Chow WS, White A, Wong KC, Tsui P, Lee ACH, Leung EKH, Woo YC, Tan KCB, Lam KSL, Lee CH and Lui DTW (2023) Cushing’s syndrome caused by ACTH precursors secreted from a pancreatic yolk sac tumor in an adult—a case report and literature review. Front. Med. 10:1246796. doi: 10.3389/fmed.2023.1246796

Received: 18 July 2023; Accepted: 20 November 2023;
Published: 05 December 2023.

Edited by:

Alessandro Vanoli, University of Pavia, Italy

Reviewed by:

Petar Brlek, St. Catherine Specialty Hospital, Croatia
Wafa Alaya, Hospital University Tahar Sfar, Tunisia

Copyright © 2023 Chang, Woo, Chow, White, Wong, Tsui, Lee, Leung, Woo, Tan, Lam, Lee and Lui. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

*Correspondence: David Tak Wai Lui, dtwlui@hku.hk

Disclaimer: All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.

From https://www.frontiersin.org/articles/10.3389/fmed.2023.1246796/full

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Ectopic Adrenocorticotropic Hormone-Secreting Pituitary Adenoma in the Clivus Region: A Case Report

Posted on September 7, 2022 by MaryO

Yan Zhang, Danrong Wu, Ruoqiu Wang, Min Luo, Dong Wang, Kaiyue Wang, Yi Ai, Li Zheng, Qiao Zhang, Lixin Shi

Department of Endocrinology and Metabolism, Guiqian International General Hospital, Guiyang, People’s Republic of China

Correspondence: Qiao Zhang; Lixin Shi, Department of Endocrinology and Metabolism, Guiqian International General Hospital, Guiyang, People’s Republic of China, Tel/Fax +86 851-86277666, Email endocrine_zq@126.com; slx1962@medmail.com.cn

Abstract: Ectopic pituitary adenoma (EPA) is a pituitary adenoma unrelated to the intrasellar component and is an extremely rare disease. EPA resembles typical pituitary adenomas in morphology, immunohistochemistry, and hormonal activity, and it may present with specific or non-specific endocrine manifestations. Here, we report a rare case of ectopic adrenocorticotropic hormone (ACTH)-secreting pituitary adenoma in the clival region. Only three patients with ACTH-secreting pituitary adenomas occurring in the clivus have been previously reported, and the present case was diagnosed as a clivus-ectopic ACTH-secreting pituitary macroadenoma. Thus, in addition to the more common organs, such as the lung, thymus, and pancreas, in the diagnosis of ectopic ACTH syndrome, special attention should be paid to the extremely rare ectopic ACTH-secreting pituitary adenoma of the clivus region.

Keywords: ectopic pituitary adenoma, Cushing’s syndrome, clivus, adrenocorticotropic hormone, endocrine

Introduction

The diagnosis of Cushing’s syndrome (CS), particularly its localization diagnosis, has always been a challenge in clinical practice.1,2 Endogenous CS can be divided into adrenocorticotropic hormone (ACTH)-dependent and non-ACTH dependent with the former accounting for 70% of CS cases. Ectopic ACTH syndrome accounts for 5–10% of CS cases, and its lesions are mainly located in the lungs, thymus, pancreas, and the thyroid gland.3 Finding such lesions in non-pituitary intracranial regions is extremely rare, and ectopic ACTH in the clivus region is even rarer. To date, less than 60 cases of ectopic ACTH-secreting pituitary adenomas have been reported,4 and determining their localization is a formidable challenge in CS diagnosis. It is difficult to make an accurate and prompt diagnosis of ectopic ACTH-secreting pituitary adenoma caused by hypercortisolism based on its clinical manifestation, routine laboratory tests, and radiologic examinations.1,4 Ectopic pituitary adenomas (EPAs) are mainly concentrated in the sphenoid sinus, suprasellar region, and cavernous sinus, and rare regions include the clivus, ethmoid sinus, and nasal cavity.5 A literature review showed that only three cases of primary EPA in the clivus region have been reported worldwide.6–8 Recently, we diagnosed a patient with ectopic ACTH-secreting pituitary macroadenoma in the clivus region that was confirmed by surgery and immunohistochemistry.

Case Presentation

A 53-year-old female patient sought medical attention at our hospital for hypertension, headache, and dizziness with a blood pressure as high as 180/100 mmHg. Her medical history showed that she had developed similar symptoms 2 years ago. At that time, she had hypertension (180/100 mmHg), headache, and dizziness, and she was treated with amlodipine (5 mg per day), benazepril hydrochloride (10 mg per day), and metoprolol tartrate (50 mg per day). The patient was not hospitalized for treatment and did not undergo systemic examination. Three months before admission, the patient had a thoracic vertebrae fracture caused by moving heavy objects. One month before admission, she had a bilateral rib fracture due to falling on flat ground. Her physical examination results were as follows: blood pressure, 160/85 mmHg; height, 147 cm; weight, 55.2 kg; and body mass index (BMI), 25.54 kg/m2. In the physical examination, moon facies, buffalo hump, concentric obesity, facial plethora, and large patches of ecchymosis at the blood sampling site were observed. Purple striae were absent below the axilla, abdomen, and limbs. Her hematological examination results were as follows: cortisol (COR) rhythm with 33.52 µg/dL (reference range: 4.26–24.85) at 8:00 AM, 34.3 µg/dL at 4:00 PM, and 33.14 µg/dL at 12:00 AM; 1 mg dexamethasone overnight suppression test indicated 22.21 µg/dL COR at 8:00 AM; 24 h urine COR was 962.16 µg/24 h (reference range: 50–437 µg/24 h); 8:00 AM ACTH at two different times was 74 pg/mL and 90.8 pg/mL (reference range: <46); high-dose dexamethasone suppression test (HDDST) was 21.44 µg/dL COR (serum COR level was not suppressed by more than 50%); serum potassium was 3.38 mmol/L (reference range: 3.5–5.5); insulin-like growth factor-1 (IGF-1) was 106.6 ng/mL (reference range: 84–236); serum luteinizing hormone (LH) was <0.07 IU/L (reference range: 1.9–12.5); serum follicle stimulating hormone (FSH) was 0.37 IU/L (reference range: 2.5–10.2); prolactin (PRL), testosterone, progesterone, and estradiol test results were normal; FT4 was 8.25 pmol/L (reference range: 10.44–24.38); TSH was 1.116 mIU/L (reference range: 0.55–4.78); oral glucose tolerance test (OGTT) indicated that fasting blood glucose was 6.3 mmol/L and 2-h blood glucose was 18.72 mmol/L; and glycated hemoglobin (HbA1c) was 7.1%. A bone mineral density test suggested osteoporosis (dual energy X-rays: L1-L4 T values were −3.4).

Magnetic resonance (MR) scans were performed using a SIGNA Pioneer 3.0T (GE Healthcare, Waukesha, WI, USA), and computed tomography (CT) scans were performed using a 256 slice CT scanner (Revolution CT; GE Healthcare, Waukesha, WI, USA). The enhanced MR scan of the sellar lesion showed a soft tissue mass with abnormal signals in the occipital bone clivus. T1WI showed an isointense signal, and T2WI showed an isointense/slightly hyperintense signal in a large area of approximately 30 mm × 46 mm. The lesion extended anteriorly to completely fill the entire sphenoidal sinus, and it was in a close proximity to the right internal carotid arteries. Significant invasion, liquefaction, and necrosis were not observed in the bilateral cavernous sinuses. Pituitary gland morphology was normal with a superoinferior diameter of 3.14 mm, and the pituitary gland was located in the center. An occipital bone clival space-occupying lesion was considered with a tendency of low malignancy and a possibility of chordoma (Figure 1A–C). Non-enhanced high-resolution CT scans of the nasal sinuses showed osteolytic destruction, and a soft tissue mass was observed in the occipital bone clivus. The mass had a large area of 20 mm × 30 mm × 46 mm (Figure 1D). Enhanced CT of the adrenals showed bilateral adrenal gland hyperplasia.

Figure 1 (A) MR T1+T2 scan (transverse view). MR T1 scan (left) shows the soft tissue mass of the occipital clivus (white arrow), and MR T2 scan (right) shows that the right internal carotid artery, cavernous sinus, and tumor are within close proximity to each other (white arrow). (B) MR T1 enhanced scan (sagittal view) shows clear demarcation between normal pituitary gland and mass (white arrow). (C) MR T2 scan (sagittal view) shows that the pituitary fossa is normally present (white arrow). (D) CT (sagittal view) shows bony destruction of dorsum sellae, clivus, and sphenoid sinus by mass (white arrow).

Bilateral inferior petrosal sinus sampling (IPSS) combined with a desmopressin stimulation test had the following results: baseline ACTH at left inferior petrosal sinus/periphery (IPS/P), 5.4; post-stimulation IPS/P, 3.42; stimulation corrected (ACTHPRL) IPS/P, 2.8; right baseline IPS/P, 1.64; post-stimulation IPS/P, 9.34; and stimulation corrected IPS/P, 6.92. The left inferior petrosal sinus was the dominant side (Table 1).

Table 1 Bilateral Inferior Petrosal Sinus Sampling Combined with Desmopressin Stimulation Test

The patient underwent endoscopic transsphenoidal clival lesion resection surgery, and the postoperative pathology test results showed EPA (Figure 2). The immunohistochemistry staining results were as follows: CK (+), SYN (+), CgA (+), ACTH (+), growth hormone (GH) (−), LH (−), TSH (−), PRL (−), FSH (−), and Ki-67 (<1% +). The COR level at 10 days after surgery was 15.87 µg/dL, and the ACTH level was 31.37 pg/mL (Table 2).

Table 2 Changes in COR and ACTH Levels During Course of Treatment
Figure 2 Pathological diagnosis of (clivus) ectopic pituitary adenoma. (A) Pituitary adenoma revealing a trabecular and nested structure revealing vascular invasion (hematoxylin and eosin (HE) stain, 200x) composed of two distinct types of cells. (B) ACTH expression in the EPA (200x, ACTH-antibody, Dako).

After admission, her blood and urine COR levels were significantly elevated, and a qualitative diagnosis of CS was obtained. Etiological examination found that ACTH was also significantly elevated, suggesting that the CS was ACTH dependent. The HDDST results showed that the serum COR level was not suppressed by more than 50% and was accompanied by hypokalemia, suggesting that the ACTH-dependent CS may be ectopic ACTH syndrome. Ectopic ACTH syndrome is relatively rare, and the lesions are caused by non-pituitary tumors. No lesions were identified in the lung, thymus, pancreas, and thyroid of our patient. Regarding the IPSS examination, the IPS/P ratio was greater than 2, which suggested that the ectopic ACTH was located intracranially and not at the periphery. Radiologic testing suggested that the pituitary structure was normal and that a space-occupying lesion in the clivus region was present. Therefore, ectopic ACTH-secreting adenoma in the clivus region was considered, and postoperative pathological biopsy was used to confirm the diagnosis.

Discussion

EPA is an extremely rare disease that occurs outside of the sella turcica, and it is not linked to the intrasellar pituitary. The morphology, immunohistochemistry, and hormone activity of EPAs are similar to typical pituitary adenomas. EPAs can manifest as specific or non-specific endocrine disorders, and they account for 0.48% of all pituitary adenomas.9 The pathogenesis of EPA is still currently unknown. It is generally considered that during the development of the anterior pituitary lobe, the incompletely degraded Rathke cleft cyst remnants of the Rathke pouch lead to the formation of EPAs in the nasopharynx, sphenoid, and clivus.10,11 EPA is rare in China. Zhu et al5 recorded 14,357 pituitary gland patients in the last 20 years; of these patients, only 14 were diagnosed with EPA (0.098% of all cases), but none of the lesions originated from the clivus region. Previous literature reviews4,5 revealed that non-functioning EPAs in the clivus region are the most common (50%); the most common hormone-secreting functional adenomas are PRL adenomas and GH adenomas, which account for 25.0% and 21.4% of EPAs, respectively, whereas ACTH-secreting EPAs are extremely rare and only account for 3.6% of cases.

The postoperative pathological and immunohistochemical results of the tumor tissue in the patient demonstrated that it was an ectopic ACTH-secreting pituitary macroadenoma in the clivus region. Most EPAs are microadenomas (diameter <1 cm), except those in the clivus region, which are macroadenomas.5 Adenoma size generally does not affect the patient’s clinical and biochemical characteristics, and it may be related to tumor location or extension.12 Encasement of the internal carotid artery is a characteristic feature of EPA invasion into surrounding tissues.5 Encasement of the right internal carotid artery by the tumor was also observed in our patient. Therefore, surgery cannot completely remove the tumor and may ultimately affect surgical outcomes, and radiotherapy may even be required in the future. The serum COR and ACTH levels of our patient were evaluated 10 days after surgery. Although the levels were significantly lower than those before the surgery, the COR level was still significantly higher than the cutoff value of 1 µg/dL,13,14 suggesting that the patient may not have complete remission due to the incomplete tumor resection in the area adjacent to the carotid artery during surgery. Another feature that was observed in our patient was bone invasion. Because the clivus is composed of abundant cancellous bone that is connected to surrounding bone structures, EPAs or other tumors may cause bone destruction and affect the sphenoidal sinus and cavernous sinus, which is also consistent with literature reports.15,16

Due to the low incidence of EPAs, most EPA cases are reported as case reports in the literature. We performed an English literature search using the PubMed and Web of Science Core Collection databases with the following predetermined terms: “Cushing’s syndrome”, “pituitary adenomas”, “clivus”, “ectopic pituitary adenoma”, and “adrenocorticotropic”. The literature was included if it met the following criteria: (i) the confirmed diagnosis of CS or ectopic ACTH syndrome was described in the literature; (ii) the diagnosis of EPA was confirmed by postoperative inspection; and (iii) EPA occurred in the clivus. After excluding cases of clival invasion from other sites, we found only three reports of ectopic ACTH-secreting adenoma in the clivus region,6–8 and they were all female patients. Ortiz-Suarez and Erickson6 employed transfrontal craniotomy to demonstrate that the ectopic ACTH-secreting adenoma was an extension of extrasellar lesion to the clivus. In a case report by Pluta et al,7 the patient was found to have cavernous sinus and clival ACTH-positive tumors through transphenoidal surgery. In a case report by Aftab et al,8 the patient only presented a space-occupying lesion with unilateral vision loss; the patient was initially diagnosed with clival chordoma, but the postoperative results supported the diagnosis of EPA. Based on preoperative imaging, the possibility of chordoma was also considered to be high in our patient. We combined the clinical manifestation and laboratory test results of the patient and considered the etiology of CS to conclude that the patient had clival ectopic ACTH-secreting adenoma instead of chordoma.

Hormone tests in our patient suggested secondary pituitary-gonadal axis and decreased pituitary-thyroid axis function. These changes in endocrine function may be due to pituitary suppression by hypercortisolism. After surgery, the corresponding markers recovered, indicating that the suppression was transient. The patient has a history of fracture and a bone mineral density suggestive of osteoporosis, which may also be associated with CS hypercortisolemia.

Treatment modalities for EPA include adenoma resection surgery, radiotherapy, and drugs. The first-line recommended treatment is surgical resection. Craniotomy is considered the surgical procedure of choice for EPA, and endoscopic transsphenoidal surgery (TSS) is considered a feasible method for preserving pituitary function while simultaneously treating EPA. However, due to limitations with the surgical operation space, there are still concerns whether sufficient exploration and effective tumor resection can be achieved.17 Because there are few case reports of such patients, the long-term outcomes of these two surgical procedures require further validation. Due to differences in EPA sites and functions, the efficacy of surgery also differs. Zhu et al5 reported that compared to the radical resection rate of sphenoidal sinus and cavernous sinus EPA (72.3% and 73.3%, respectively), the radical resection rate of clival EPA is only 45.0%, and this difference is statistically significant.

The three clival EPA patients described in the three relevant publications6–8 all showed significant improvements in postoperative signs, symptoms, and hormone levels after complete surgical removal of the lesions or combined with radiation therapy. In our patient, however, radical resection of the tumor could not be achieved due to the close proximity of the tumor mass to the right internal carotid artery, and surgery could not be used to achieve complete remission, which is similar to the case reported by Zhu et al.5 For such patients, radiotherapy can be considered as a second-line treatment for EPA. To control hormone levels, drugs and bilateral adrenalectomy are also treatment options.5,18,19

Conclusion

EPA is a rare disease, and clival EPA is even rarer. From the entire diagnosis and treatment course, this unique and rare EPA case was preliminarily diagnosed through a comprehensive hormone panel and IPSS, and it was confirmed by pathology and immunohistochemistry after surgery. In the diagnosis of ectopic ACTH syndrome, attention should also be paid to extremely rare pituitary ectopic sites, such as the sphenoid sinuses, parasellar region, and the clivus, in addition to common sites, such as the lungs, thymus, pancreas, and thyroid.

Data Sharing Statement

The raw data supporting the conclusions of this article will be made available by the authors without undue reservation.

Informed Consent Statement

Prior written permission was obtained from the patient for treatment as well as for the preparation of this manuscript and for publication. Our institution approved the publication of the case details.

Acknowledgments

We would like to thank the patient and her family.

Author Contributions

All authors made a significant contribution to the work reported, whether that is in the conception, study design, execution, acquisition of data, analysis and interpretation, or in all these areas; took part in drafting, revising or critically reviewing the article; gave final approval of the version to be published; have agreed on the journal to which the article has been submitted; and agree to be accountable for all aspects of the work.

Funding

There is no funding to report.

Disclosure

The authors report no conflicts of interest in this work.

References

1. Senanayake R, Gillett D, MacFarlane J, et al. New types of localization methods for adrenocorticotropic hormone-dependent Cushing’s syndrome. Best Pract Res Clin Endocrinol Metab. 2021;35:101513. doi:10.1016/j.beem.2021.101513

2. Young J, Haissaguerre M, Viera-Pinto O, et al. Management of Endocrine Disease: cushing’s syndrome due to ectopic ACTH secretion: an expert operational opinion. Eur J Endocrinol. 2020;182:R29–r58. doi:10.1530/EJE-19-0877

3. Hayes AR, Grossman AB. The ectopic adrenocorticotropic hormone syndrome: rarely easy, always challenging. Endocrinol Metab Clin North Am. 2018;47:409–425. doi:10.1016/j.ecl.2018.01.005

4. Zhu J, Lu L, Yao Y, et al. Long-term follow-up for ectopic ACTH-secreting pituitary adenoma in a single tertiary medical center and a literature review. Pituitary. 2020;23:149–159. doi:10.1007/s11102-019-01017-y

5. Zhu J, Wang Z, Zhang Y, et al. Ectopic pituitary adenomas: clinical features, diagnostic challenges and management. Pituitary. 2020;23:648–664. doi:10.1007/s11102-020-01071-x

6. Ortiz-Suarez H, Erickson DL. Pituitary adenomas of adolescents. J Neurosurg. 1975;43:437–439. doi:10.3171/jns.1975.43.4.0437

7. Pluta RM, Nieman L, Doppman JL, et al. Extrapituitary parasellar microadenoma in Cushing’s disease. J Clin Endocrinol Metab. 1999;84:2912–2923. doi:10.1210/jcem.84.8.5890

8. Aftab HB, Gunay C, Dermesropian R, et al. “An Unexpected Pit” – ectopic pituitary adenoma. J Endocr Soc. 2021;5:A557–A558. doi:10.1210/jendso/bvab048.1137

9. Li X, Zhao B, Hou B, et al. Case report and literature review: ectopic thyrotropin-secreting pituitary adenoma in the suprasellar region. Front Endocrinol. 2021;12:619161. doi:10.3389/fendo.2021.619161

10. Agely A, Okromelidze L, Vilanilam GK, et al. Ectopic pituitary adenomas: common presentations of a rare entity. Pituitary. 2019;22:339–343. doi:10.1007/s11102-019-00954-y

11. Tajudeen BA, Kuan EC, Adappa ND, et al. Ectopic pituitary adenomas presenting as sphenoid or clival lesions: case series and management recommendations. J Neurol Surg B Skull Base. 2017;78:120–124. doi:10.1055/s-0036-1592081

12. Akirov A, Shimon I, Fleseriu M, et al. Clinical study and systematic review of pituitary microadenomas vs. macroadenomas in cushing’s disease: does size matter? J Clin Med. 2022;11:1558. doi:10.3390/jcm11061558

13. Badiu C. Williams textbook of endocrinology. Acta Endocrinologica. 2019;15:416. doi:10.4183/aeb.2019.416

14. Rollin GA, Ferreira NP, Junges M, et al. Dynamics of serum cortisol levels after transsphenoidal surgery in a cohort of patients with Cushing’s disease. J Clin Endocrinol Metab. 2004;89:1131–1139. doi:10.1210/jc.2003-031170

15. Hu S, Cheng S, Wu Y, et al. A large cavernous sinus giant cell tumor invading clivus and sphenoid sinus masquerading as meningioma: a case report and literature review. Front Surg. 2022;9:861739. doi:10.3389/fsurg.2022.861739

16. Wu X, Ding H, Yang L, et al. Invasive corridor of clivus extension in pituitary adenoma: bony anatomic consideration, surgical outcome and technical nuances. Front Oncol. 2021;11:689943. doi:10.3389/fonc.2021.689943

17. Sun X, Lu L, Feng M, et al. Cushing syndrome caused by ectopic adrenocorticotropic hormone-secreting pituitary adenomas: case report and literature review. World Neurosurg. 2020;142:75–86. doi:10.1016/j.wneu.2020.06.138

18. Szabo Yamashita T, Sada A, Bancos I, et al. Differences in outcomes of bilateral adrenalectomy in patients with ectopic ACTH producing tumor of known and unknown origin. Am J Surg. 2021;221:460–464. doi:10.1016/j.amjsurg.2020.08.047

19. Szabo Yamashita T, Sada A, Bancos I, et al. Bilateral adrenalectomy: differences between cushing disease and Ectopic ACTH-producing tumors. Ann Surg Oncol. 2020;27:3851–3857. doi:10.1245/s10434-020-08451-4

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