Cushing Syndrome Caused by an Ectopic ACTH-Producing Pituitary Adenoma of the Clivus Region

Abstract

Rationale:

Ectopic ACTHproducing pituitary adenoma (EAPA) of the clivus region is extraordinarily infrequent condition and merely a few reports have been reported to date.

Patient concerns:

The patient was a 53-year-old woman who presented with Cushing-like appearances and a soft tissue mass in the clivus region.

Diagnoses:

The final diagnosis of clivus region EAPA was established by clinical, radiological and histopathological findings.

Interventions:

The patient underwent gross total clivus tumor resection via transsphenoidal endoscopy.

Outcomes:

Half a year after surgery, the patient Cushing-like clinical manifestations improved significantly, and urinary free cortisol and serum adrenocorticotropin (ACTH) returned to normal.

Lessons:

Given the extreme scarcity of these tumors and their unique clinical presentations, it may be possible to misdiagnose and delayed treatment. Accordingly, it is especially crucial to summarize such lesions through our present case and review the literature for their precise diagnosis and the selection of optimal treatment strategies.

1. Introduction

Pituitary adenoma arises from the anterior pituitary cells and is the commonest tumor of the sellar region.[1] It makes up approximately 10% to 15% of all intracranial tumors.[2] Ectopic pituitary adenoma (EPA) is defined as a pituitary adenoma that occurs outside the sellar area and has no direct connection to normal pituitary tissue.[3] The most frequent sites of EPA are the sphenoid sinus and suprasellar region, and much less frequent sites including the clivus region, cavernous sinus, and nasopharynx.[4]

Hypercortisolism and the series of symptoms it leads to is termed Cushing syndrome (CS).[5] CS is classified into adrenocorticotropin (ACTH)-dependent and ACTH-independent CS depending on the cause, accounting for 80% to 85% and 15% to 20% of cases, respectively.[6] Pituitary adenoma accounts for ACTH-dependent CS 75% to 80%, while ectopic ACTH secretion accounts for the remaining 15% to 20%.[7] Ectopic CS is a very rare disorder of CS caused by an ACTH-secreting tumor outside the pituitary or adrenal gland.[8] It has been reported that ectopic ACTHproducing pituitary adenoma (EAPA) can occur in the sphenoid sinus, cavernous sinus, clivus, and suprasellar region,[9] with EAPA in the clivus region being extremely rare, and merely 6 cases have been reported in the English literature (Table 1).[10–15] Furthermore, as summarized in the Table 1, EAPA in the clivus area has unique symptoms, which may lead to misdiagnosis as well as delay in treatment. Therefore, we herein described a case of CS from an EAPA of the clivus region and reviewed relevant literature for the purpose of further understanding this extraordinarily unusual condition.

Table 1 – Literature review of cases of primary clival ectopic ACTHproducing pituitary adenoma (including the current case).

Reference Age (yr)/sex Symptoms Imaging findings Maximum tumor diameter (mm) Preoperative elevated hormone IHC Surgery RT Follow-up (mo) Outcome
Ortiz et al 1975[10] 15/F NA NA NA NA NA Right transfrontal craniotomy, NA Yes NA Symptomatic relief
Anand et al 1993[11] 58/F Anosphrasia, blurred vision, occasional left frontal headache, Routine radiographic evaluation revealed a clival tumor and nasopharyngeal mass with bone erosion. MRI demonstrated a Midline homogeneous mass. 30 ACTH ACTH in a few isolated cells Maxillotomy approach, GTR Yes 12 Symptomatic relief
Pluta et al 1999[12] 20/F Cushing syndrome MRI revealed a hypodense contrast-enhancing lesion. NA ACTH ACTH Transsphenoidal surgery, GTR No 18 Symptomatic relief
Shah et al 2011[13] 64/M Facial paresthesias, myalgias, decreased muscle strength, and fatigue CT imaging showed a clival mass. 21 ACTH ACTH NA, GTR No 7 Symptomatic relief
Aftab et al 2021[14] 62/F Transient unilateral visual loss MRI showed a T2 heterogeneously enhancing hyperintense lesion. 21 No ACTH Transsphenoidal resection, GTR NO 6 Symptomatic relief
Li et al 2023[15] 47/F Bloody nasal discharge, dizziness and headache CT revealed an ill-defined mass eroding the adjacent bone. MRI T1 showed a heterogeneous mass with hypointensity, hyperintensity on T2-weighted images and isointensity on diffusion-weighted images. 58 NA ACTH Transsphenoidal endoscopy, STR Yes 2 Symptomatic relief
Current case 53/F Headache, and dizziness, Cushing syndrome CT demonstrated bone destruction and a soft tissue mass. MRI T1 revealed irregular isointense signal, and MRI T2 showed isointense signal/slightly high signal. 46 ACTH ACTH Transsphenoidal endoscopy, GTR NO 6 Symptomatic relief
ACTH = adrenocorticotropin, CT = computed tomography, GTR = gross total resection, IHC = immunohistochemistry, MRI = magnetic resonance imaging, NA = not available, RT = radiotherapy, STR = subtotal resection.

2. Case presentation

A 53-year-old female presented to endocrinology clinic of our hospital with headache and dizziness for 2 years and aggravated for 1 week. Her past medical history was hypertension, with blood pressure as high as 180/100 mm Hg. Her antihypertensive medications included amlodipine besylate, benazepril hydrochloride, and metoprolol tartrate, and she felt her blood pressure was well controlled. In addition, she suffered a fracture of the thoracic vertebrae 3 month ago; and bilateral rib fractures 1 month ago. Physical examination revealed that the patient presented classical Cushing-like appearances, including moon face and supraclavicular and back fat pads, and centripetal obesity (body mass index, 25.54 kg/m2) with hypertension (blood pressure, 160/85 mm Hg).

Laboratory studies revealed high urinary free cortisol levels at 962.16 µg/24 hours (reference range, 50–437 µg/24 hours) and absence of circadian cortisol rhythm (F [0am] 33.14 µg/dL, F [8am] 33.52 µg/dL, F [4pm] 33.3 µg/dL). ACTH levels were elevated at 90.8 pg/mL (reference range, <46 pg/mL). The patient low-dose dexamethasone suppression test demonstrated the existence of endogenous hypercortisolism. High-dose dexamethasone suppression test results revealed that serum cortisol levels were suppressed by <50%, suggesting the possibility of ectopic ACTH-dependent CS. Serum luteinizing hormone and serum follicle stimulating hormone were at low levels, <0.07 IU/L (reference range, 15.9–54.0 IU/L) and 2.57 IU/L (reference range, 23.0–116.3 IU/L), respectively. Insulin-like growth factor-1, growth hormone (GH), prolactin (PRL), thyroid stimulating hormone, testosterone, progesterone and estradiol test results are all normal. Oral glucose tolerance test showed fasting glucose of 6.3 mmol/L and 2-hour glucose of 18.72 mmol/L; glycosylated hemoglobin (HbA1c) was 7.1%. Serum potassium fluctuated in the range of 3.14 to 3.38 mmol/L (reference range, 3.5–5.5 mmol/L), indicating mild hypokalemia.

High-resolution computed tomography (CT) scan of the sinuses revealed osteolytic bone destruction of the occipital clivus and a soft tissue mass measuring 20 mm × 30 mm × 46 mm (Fig. 1A). The mass filled the bilateral sphenoid sinuses and involved the cavernous sinuses, but the pituitary was normal. Cranial MR scan showed the T1W1 isointense signal and the T2W1 isointense signal/slightly high signal in the sphenoid sinus and saddle area (Fig. 1B–D). Bone density test indicated osteoporosis.

F1
Figure 1.: 

Radiological findings. (A) CT demonstrated bone destruction and a soft tissue mass on the occipital clivus (white arrow). (B) Axial view of the MR T1 revealed irregular isointense signal in the sphenoid sinus and saddle area (white arrow). (C and D) Axial view and sagittal view of the MR T2 showed isointense signal/slightly high signal in the sphenoid sinus and saddle area (black arrow). CT = computed tomography.

Subsequently, the patient underwent gross total clivus tumor resection via transsphenoidal endoscopy. During surgery, the tumor was found to be light red in color with a medium texture, and the tumor tissue protruded into the sphenoidal sinus cavity and eroded the clival area. Histologically, the tumor cells were nested, with interstitially rich blood sinuses and organoid arrangement (Fig. 2A). The tumor cells were relatively uniform in size, with light red cytoplasm, delicate pepper salt-like chromatin, and visible nucleoli (Fig. 2B). In addition, mitosis of tumor cells was extremely rare. Immunohistochemically, the neoplasm cells were diffuse positive for CK (Fig. 2C), CgA (Fig. 2D), ACTH (Fig. 2E), Syn and CAM5.2, with low Ki-67 labeling index (<1%) (Fig. 2F). Simultaneously, all other pituitary hormone markers like GH, thyroid stimulating hormone, PRL, luteinizing hormone, as well as follicle stimulating hormone were negatively expressed. On the basis of these medically historical, clinical, laboratorial, morphologic, and immunohistochemical findings, the final pathological diagnosis of an EAPA was established.

F2
Figure 2.: 

HE and immunohistochemical findings. (A) Histologic sections revealed morphologically homogeneous tumor cells in nests with a prominent and delicate vascularized stroma (H&E, × 200). (B) The tumor cells had fine chromatin with visible nuclei and rare mitoses (H&E, × 400). CK (C), CgA (D) and ACTH (E) immunohistochemically showed diffuse reactivity of the tumor cells (SP × 200). (F) The proliferation index is <1% on Ki-67 staining (SP × 200).

When evaluated 2 months after surgery, her Cushing-like characteristics had well improved, and her blood pressure was normal. Furthermore, her serum cortisol and ACTH returned to the normal levels. Six-month postoperative follow-up revealed that serum cortisol and ACTH were stable at normal levels, and no signs of tumor recurrence were detected on imaging.

3. Discussion

EAPA is defined as an ACTH-secreting ectopic adenoma located outside the ventricles, and has no continuity with the normal intrasellar pituitary gland.[9] ACTH promotes cortisol secretion by stimulating the adrenal cortical fasciculus. The clinical manifestations of hypercortisolism are diverse, and the severity is partly related to the duration of the cortisol increase.[8] Clival tumors are typically uncommon, accounting for 1% of all intracranial tumors. There are many differential diagnoses for clival lesions, including the most common chordoma (40%), meningioma, chondrosarcoma, astrocytoma, craniopharyngioma, germ cell tumors, non-Hodgkin lymphoma, melanoma, metastatic carcinoma, and rarely pituitary adenoma.[16] The commonest clival EPA is a PRL adenoma, followed by null cell adenoma, and the least common are ACTH adenoma and GH adenoma.[2] The clival EAPA is extremely unwonted, and only 6 other cases apart from ours have been reported in literature so far (Table 1).

The average age of the patients with these tumors was 48 years (range, 15–64 years). There was a obvious female predominance with a female-to-male prevalence ratio of 6:1. Only 2 patients (2/6, 33.3%) with reported clinical symptoms, including our patients, presented with overt clinical manifestations of CS. Compression of the mass on adjacent structures (e.g., nerves) may result in anosphrasia, visual impairment, headache, myalgias, decreased muscle strength, dizziness and facial sensory abnormalities. The diagnosis and localization of these tumors relied heavily on radiological imaging. Head MRI was the most basic method used for them detection, for localization adenomas and their invasion of surrounding structures to guide the choice of treatment and surgical options methods. Radiographic characteristics had been reported in 6 patients with EAPA in the clivus region. All of these patients (6/6, 100%) had initial positive findings of sellar MRI (or CT) identifying an ectopic adenoma before surgery. MR T1 was usually a low-intensity or isointense signal, while MR T2 was usually an isointense or slightly higher signal. The maximum diameter of the tumor was reported in 5 cases, with the mean maximum diameter was 35.2 mm (range, 21–55 mm) according to preoperative MRI and intraoperative observations. As summarized in Table 1, 4/5 clival EAPA cases secreted ACTH. Histologically, all cases (6/6, 100%) expressed ACTH scatteredly or diffusely.

The gold standard for the treatment of CS caused by EAPA was the surgical removal of EPA, which was essential to achieve remission and histological confirmation of the disease.[9] The most common method of EAPA resection in the clivus region was transsphenoidal sinus resection (4/6, 66.67%), followed by craniotomy (1/6, 16.67%) and maxillary osteotomy (1/6, 16.67%). Transsphenoidal endoscopic surgery allowed resection of the EAPA and manipulation of neurovascular structures and avoidance of cerebral atrophy, whereas craniotomy allowed full exposure of the suprasellar region, direct visualization or manipulation of the adenoma, and reduced the risk of postoperative CSF leak.[9] Both approaches had their advantages, and there was no consensus on which surgical approach was best for the treatment of EAPA in the slope area.[9] The choice of the best surgical approach was believed to be based on the condition of the adenoma, as well as the general condition of the patient and the experience of the surgeon.[9] As summarized in Table 1, most complete tumor resections were achieved regardless of the method chosen. A minority of patients underwent postoperative radiotherapy (3/7, 42.86%), and most of them had invasion of the surrounding bone tissue. All patients experienced effective postoperative relief of symptoms.

In summary, due to the rarity of this disorder, an accurate preoperative diagnosis of EAPA in the slope area is extremely challenging for the clinician or radiologist. The final precise diagnosis relies on a combination of clinical symptoms, imaging findings, histology and immunohistochemical markers. For this type of tumor, surgery is an effective treatment to relieve the clinical manifestations caused by tumor compression or hormonal secretion. The choice of postoperative adjuvant radiotherapy is mainly based on the presence of invasion of the surrounding bone tissue. Further cases may be necessary to summarize the clinical features of such lesions and to develop optimal treatment strategies.

Acknowledgments

We would like to thank the patient and her family.

Author contributions

Conceptualization: Yutao He.

Data curation: Ziyi Tang.

Formal analysis: Na Tang.

Methodology: Yu Lu, Fangfang Niu, Jiao Ye, Zheng Zhang, Chenghong Fang.

Writing – original draft: Yutao He.

Writing – review & editing: Yutao He, Lei Yao.

Abbreviations:

ACTH
adrenocorticotropin
CS
cushing syndrome
CT
computed tomography
EAPA
ectopic ACTHproducing pituitary adenoma
EPA
ectopic pituitary adenoma
GH
growth hormone
PRL
prolactin

References

[1]. Gittleman H, Ostrom QT, Farah PD, et al. Descriptive epidemiology of pituitary tumors in the United States, 2004-2009. J Neurosurg. 2014;121:527–35.

[2]. Karras CL, Abecassis IJ, Abecassis ZA, et al. Clival ectopic pituitary adenoma mimicking a Chordoma: case report and review of the literature. Case Rep Neurol Med. 2016;2016:8371697.

[3]. Bălaşa AF, Chinezu R, Teleanu DM, et al. Ectopic intracavernous corticotroph microadenoma: case report of an extremely rare pathology. Rom J Morphol Embryol. 2017;58:1447–51.

[4]. Zhu J, Wang Z, Zhang Y, et al. Ectopic pituitary adenomas: clinical features, diagnostic challenges and management. Pituitary. 2020;23:648–64.

[5]. Paleń-Tytko JE, Przybylik-Mazurek EM, Rzepka EJ, et al. Ectopic ACTH syndrome of different origin-diagnostic approach and clinical outcome. experience of one clinical centre. PLoS One. 2020;15:e0242679.

[6]. Sharma ST, Nieman LK, Feelders RA. Cushing’s syndrome: epidemiology and developments in disease management. Clin Epidemiol. 2015;7:281–93.

[7]. Aniszewski JP, Young WF Jr, Thompson GB, et al. Cushing syndrome due to ectopic adrenocorticotropic hormone secretion. World J Surg. 2001;25:934–40.

[8]. Mohib O, Papleux E, Remmelink M, et al. An ectopic Cushing’s syndrome as a cause of severe refractory hypokalemia in the ICU. Acta Clin Belg. 2021;76:373–8.

[9]. 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.

[10]. Ortiz-Suarez H, Erickson DL. Pituitary adenomas of adolescents. J Neurosurg. 1975;43:437–9.

[11]. Anand VK, Osborne CM, Harkey HL. Infiltrative clival pituitary adenoma of ectopic origin. Otolaryngol Head Neck Surg. 1993;108:178–83.

[12]. Pluta RM, Nieman L, Doppman JL, et al. Extrapituitary parasellar microadenoma in Cushing’s disease. J Clin Endocrinol Metab. 1999;84:2912–23.

[13]. Shah R, Schniederjan M, DelGaudio JM, et al. Visual vignette.s Ectopic ACTH-secreting pituitary adenoma. Endocr Pract. 2011;17:966.

[14]. Aftab HB, Gunay C, Dermesropian R, et al. “An Unexpected Pit” – ectopic pituitary adenoma. J Endocr Soc. 2021;5:A557–8.

[15]. Li Y, Zhu JG, Li QQ, et al. Ectopic invasive ACTH-secreting pituitary adenoma mimicking chordoma: a case report and literature review. BMC Neurol. 2023;23:81.

[16]. Wong K, Raisanen J, Taylor SL, et al. Pituitary adenoma as an unsuspected clival tumor. Am J Surg Pathol. 1995;19:900–3.

Hide full references list
Keywords:

clivus regionCushingEctopic ACTHlike appearanceproducing pituitary adenoma

From https://journals.lww.com/md-journal/Fulltext/2023/06230/Cushing_syndrome_caused_by_an_ectopic.32.aspx

Sparsely Granulated Corticotroph Pituitary Macroadenoma Presenting with Pituitary Apoplexy Resulting in Remission of Hypercortisolism

https://doi.org/10.1016/j.aace.2022.04.003Get rights and content
Under a Creative Commons license
Open access

Highlights

• We describe a rare case of a patient with a sparsely granulated corticotroph pituitary macroadenoma with pituitary apoplexy who underwent transsphenoidal resection resulting in remission of hypercortisolism.
• Corticotroph adenomas are divided into densely granulated, sparsely granulated and Crooke’s cell tumors.
• macroadenomas account for 7-23% of patients with pituitary corticotroph adenomas
• Sparsely granulated corticotroph tumors are associated with longer duration of Cushing disease prior to diagnosis, larger tumor size at diagnosis, decreased immediate remission rate, increased proliferative marker Ki-67 and increased recovery time of hypothalamic-pituitary-adrenal axis after surgery.
• Granulation pattern is an important clinicopathological distinction impacting the behavior and treatment outcomes of pituitary corticotroph adenomas

Abstract

Background

/Objective: Pituitary corticotroph macroadenomas, which account for 7% to 23% of corticotroph adenomas, rarely present with apoplexy. The objective of this report is to describe a patient with a sparsely granulated corticotroph tumor (SGCT) presenting with apoplexy and remission of hypercortisolism.

Case Report

A 33-year-old male presented via ambulance with sudden onset of severe headache and nausea/vomiting. Physical exam revealed bitemporal hemianopsia, diplopia from right-sided third cranial nerve palsy, abdominal striae, facial plethora, dorsal and supraclavicular fat pad. Magnetic resonance imaging (MRI) demonstrated a 3.2 cm mass arising from the sella turcica with hemorrhage compressing the optic chiasm, extension into the sphenoid sinus and cavernous sinus. Initial investigations revealed plasma cortisol of 64.08 mcg/dL (Reference Range (RR), 2.36 – 17.05). He underwent emergent transsphenoidal surgery. Pathology was diagnostic of SGCT. Post-operatively, cortisol was <1.8ug/dL (RR, 2.4 – 17), adrenocorticotropic hormone (ACTH) 36 pg/mL (RR, 0 – 81), thyroid stimulating hormone (TSH) 0.07 uIU/mL (RR, 0.36 – 3.74), free thyroxine 1 ng/dL (RR, 0.8 – 1.5), luteinizing hormone (LH) <1 mIU/mL (RR, 1 – 12), follicle stimulating hormone (FSH) 1 mIU/mL (RR, 1 – 12) and testosterone 28.8 ng/dL (RR, 219.2 – 905.6) with ongoing requirement for hydrocortisone, levothyroxine, testosterone replacement and continued follow-up.

Discussion

Corticotroph adenomas are divided into densely granulated, sparsely granulated and Crooke’s cell tumors. Sparsely granulated pattern is associated with larger tumor size and decreased remission rate after surgery.

Conclusion

This report illustrates a rare case of hypercortisolism remission due to apoplexy of a SGCT with subsequent central adrenal insufficiency, hypothyroidism and hypogonadism.

Keywords

pituitary apoplexy
pituitary macroadenoma
pituitary tumor
sparsely granulated corticotroph tumor
Cushing disease

Introduction

The incidence of Cushing Disease (CD) is estimated to be between 0.12 to 0.24 cases per 100,00 persons per year1,2. Of these, 7-23% are macroadenomas (>1 cm)345. Pituitary apoplexy is a potentially life-threatening endocrine and neurosurgical emergency which occurs due to infarction or hemorrhage in the pituitary gland. Apoplexy occurs most commonly in non-functioning macroadenomas with an estimated prevalence of 6.2 cases per 100,000 persons and incidence of 0.17 cases per 100,00 persons per year6. Corticotroph macroadenoma presenting with apoplexy is uncommon with only a handful of reports in the literature7. We present a case of a sparsely granulated corticotroph (SGCT) which presented with apoplexy leading to remission of hypercortisolism and subsequent central adrenal insufficiency.

Case Presentation

A 33-year-old male who was otherwise healthy and not on any medications presented to a community hospital with sudden and severe headache accompanied by hypotension, nausea, vomiting, bitemporal hemianopsia and diplopia. Computed Tomography (CT) scan of the brain demonstrated a hyperattenuating 2.0 cm x 2.8 cm x 1.5 cm mass at the sella turcica with extension into the right cavernous sinus and encasement of the right internal carotid arteries (Figure 1A). He was transferred to a tertiary care center for neurosurgical management with endocrinology consultation post-operatively.

  1. Download : Download high-res image (404KB)
  2. Download : Download full-size image

Figure 1. hyperattenuating 2.0 cm x 2.8 cm x 1.5 cm mass at the sella turcica on unenhanced CT (A); MRI demonstrated a 1.9 cm x 3.2 cm x 2.4 cm heterogeneous mass on T1 (B) and T2-weighted imaging (C) showing small hyperintense areas in solid part of the sella mass with flattening of the optic chiasm, remodeling/dehiscence of the floor of the sella and extending into the right cavernous sinus with at least partial encasement of the ICA

In retrospect, he reported a 3-year history of ongoing symptoms of hypercortisolism including increased central obesity, dorsal and supraclavicular fat pad, facial plethora, abdominal purple striae, easy bruising, fatigue, decreased libido and erectile dysfunction. Notably, at the time of presentation he did not have a history of diabetes, hypertension, osteoporosis, fragility fractures or proximal muscle weakness. He fathered 2 children previously. His physical examination was significant for Cushingoid facies, facial plethora, dorsal and supraclavicular fat pads and central obesity with significant axillary and abdominal wide purple striae (Figure 2). Neurological examination revealed bitemporal hemianopsia, right third cranial nerve palsy with ptosis and impaired extraocular movement. The fourth and sixth cranial nerves were intact as was the rest of his neurological exam. These findings were corroborated by Ophthalmology.

  1. Download : Download high-res image (477KB)
  2. Download : Download full-size image

Figure 2. Representative images illustrating facial plethora (A); abdominal striae (B, C); supraclavicular fat pad (D); dorsal fat pad (E)

Initial laboratory data at time of presentation to the hospital included elevated plasma cortisol of 64.08ug/dL (RR, 2.36 – 17.05), ACTH was not drawn at the time of presentation, normal TSH 0.89 mIU/L (RR, 0.36 – 3.74), free thyroxine 0.91ng/dL (RR, 0.76 – 1.46), evidence of central hypogonadism with low total testosterone 28.8 ng/dL (RR, 219.2 – 905.6) and inappropriately normal luteinizing hormone (LH) 1mIU/mL (RR, 1 – 12) and follicle stimulating hormone (FSH) 3mIU/mL (RR, 1 – 12), low prolactin <1 ng/mL (RR, 3 – 20), and normal insulin growth factor – 1 (IGF–1) 179ng/mL (RR, 82 – 242).

A pituitary gland dedicated MRI was performed to further characterize the mass, which re-demonstrated a 1.9 cm x 3.2 cm x 2.4 cm heterogenous mass at the sella turcica extending superiorly and flattening the optic chiasm, remodeling of the floor of the sella and bulging into the sphenoid sinus and extending laterally into the cavernous sinus with encasement of the right internal carotid artery (ICA). As per the radiologist’s diagnostic impression, this appearance was most in keeping with a pituitary macroadenoma with apoplexy (Figure 1B – C).

The patient underwent urgent TSS and decompression with no acute complications. Pathological examination of the pituitary adenoma showed features characteristic of sparsely granulated corticotroph pituitary neuroendocrine tumor (adenoma)8, with regional hemorrhage and tumor necrosis (apoplexy). The viable tumor exhibited a solid growth pattern (Figure 3A), t-box transcription factor (T-pit) nuclear immunolabeling (Figure 3B), diffuse cytoplasmic CAM5.2 (low molecular weight cytokeratin) immunolabeling (Figure 3C), and regional weak to moderate intense granular cytoplasmic ACTH immuno-staining (Figure 3D). The tumor was immuno-negative for: pituitary-specific positive transcription factor 1 (Pit-1) and steroidogenic factor 1 (SF-1) transcription factors, growth hormone, prolactin, TSH, FSH, LH, estrogen receptor-alpha, and alpha-subunit. Crooke hyalinization was not identified in an adjacent compressed fragment of non-adenomatous anterior pituitary tissue. Ki-67 immunolabeling showed a 1.5% proliferative index (11 of 726 nuclei).

  1. Download : Download high-res image (2MB)
  2. Download : Download full-size image

Figure 3. Hematoxylin phloxine saffron staining showing adenoma with solid growth pattern (A); immunohistochemical staining showing T-pit reactivity of tumor nuclei (B); diffuse cytoplasmic staining for cytokeratin CAM5.2 (C); and regional moderately intense granular cytoplasmic staining for ACTH (D). Scale bar = 20 μm

Post-operatively, he developed transient central diabetes insipidus requiring desmopressin but resolved on discharge. His postoperative cortisol was undetectable, ACTH 36 pg/mL (RR, 0 – 81), TSH 0.07 mIU/mL (RR, 0.36 – 3.74), free thyroxine 1 ng/dL (RR, 0.8 – 1.5), LH <1mIU/mL (RR, 1 – 12), FSH 1 mIU/mL (RR, 1 – 12) and testosterone 28.8 ng/dL (RR, 219.2 – 905.6) (Table 1 and Figure 4). One month later, he reported 15 pounds of weight loss and a 5-inch decrease in waist circumference. He also noted a reduction in the dorsal and supraclavicular fat pads, facial plethora, and Cushingoid facies as well as fading of the abdominal stretch marks. His visual field defects and right third cranial nerve palsy resolved on follow up with ophthalmology post-operatively. Repeat MRI six months post-operatively showed minor residual soft tissue along the floor of the sella. He is being followed by Neurosurgery, Ophthalmology, and Endocrinology for monitoring of disease recurrence, visual defects, and management of hypopituitarism.

Table 1. Pre- and post-operative hormonal panel

POD -1 POD 0 POD1 POD2 POD3 POD16 6 -9 months Comments
Cortisol(2.4 – 17 ug/dL) 64↓ 32↓ 11↓ <1.8↓ <1.8↓ 1.8↓ HC started POD3 post bloodwork
ACTH(0 – 81 pg/mL) 41↓ 36↓ 28↓ 13↓
TSH(0.36 – 3.74 uIU/mL) 0.89 0.43 0.12↓ 0.07↓ 0.05↓ 0.73
Thyroxine, free(0.8 – 1.5 ng/dL) 0.9 0.9 1.1 1 2.1↑ 1 Levothyroxine started POD4
LH(1 – 12 miU/mL) 1↓ <1↓ 1↓ 3
FSH(1 – 12 mIU/mL) 3↓ 1↓ 1↓ 3
Testosterone(219.2 – 905.6 ng/dL) 28.8↓ <20↓ 175.9↓ Testosterone replacement started as outpatient
Testosterone, free(160 – 699 pmol/L) <5.8↓ 137↓
IGF-1(82 – 242 ng/mL) 179 79
GH(fasting < 6 mIU/L) 4.5 <0.3
Prolactin(3 – 20 ng/mL) <1↓ <1↓

POD, postoperative day; HC, hydrocortisone; ACTH, adrenocorticotropic hormone; TSH, thyroid stimulating hormone; LH, luteinizing Hormone; FSH, follicle stimulating hormone; IGF-1, insulin like growth factor – 1; GH, growth hormone

  1. Download : Download high-res image (259KB)
  2. Download : Download full-size image

Figure 4. Trend of select pituitary hormonal panel with key clinical events denoted by black arrows.

Discussion

Microadenomas account for the majority of corticotroph tumors, but 7% – 23% of patients are diagnosed with a macroadenoma345. It is even rarer for a corticotroph macroadenoma to present with apoplexy with only a handful of case reports or series in the literature7. Due to its rarity, appropriate biochemical workup on presentation, such as including an ACTH with the blood work, may be omitted especially if the patient is going for emergent surgery. In this case, the undetectable prolactin can reflect loss of anterior pituitary function and also suggest a functioning corticotroph adenoma due to the inhibitory effect of long term serum glucocorticoids on prolactin secretion9. After undergoing TSS, the patient developed central adrenal insufficiency, hypothyroidism and hypogonadism requiring hormone replacement. Presumably, the development of adrenal insufficiency demonstrated the remission of hypercortisolism as a result of apoplexy and/or TSS. The ACTH remains detectable likely representing residual tumor that was not obliterated by apoplexy nor excised by TSS given it location near the carotid artery and cavernous sinus. The presence of adrenal insufficiency in the setting of detectable ACTH is not contradictory as the physiological hypothalamic-pituitary-adrenal axis has been suppressed by the long-term pathological production of ACTH. IGF-1 and prolactin also failed to recover post-operatively. In CD where the production of IGF-1 and prolactin are attenuated by elevated cortisol, it would then be expected that IGF-1 and prolactin recover after hypercortisolism remission. However, the absence of this observation in our case is likely a sequalae of the apoplexy and extensive surgery leading to pituitary hypofunction.

We also want to highlight features of the pre-operative radiographical findings which can provide valuable insight into the subsequent histology. Previous literature has shown that, on T2-weight MRI, silent corticotroph adenomas are strongly correlated with characteristic a multimicrocystic appearance while nonfunctional gonadotroph macroadenomas are not correlated with this MRI finding10. The multimicrocystic appearance is described as small hyperintense areas with hyperintense striae in the solid part of the tumor (Figure 1C)10. This is an useful predictive tool for silent corticotroph adenomas with a sensitivity of 76%, specificity of 95% and a likelihood ratio of 15.310.

The ability to distinguish between silent corticotroph macroadenoma and other macroadenomas is important for assessing rate of remission and recurrence risk. In 2017, the WHO published updated classification for pituitary tumors. In this new classification, corticotroph adenomas are further divided into densely granulated, sparsely granulated and Crooke’s cell tumors11. DGCT are intensely Periodic Acid Schiff (PAS) stain positive and exhibit strong diffuse pattern of ACTH immunoreactivity, whereas SGCT exhibit faintly positive PAS alongside weak focal ACTH immunoreactivity4,12. Crooke’s cell tumors are characterized by Crooke’s hyaline changes in more than 50% of the tumor cells4. In the literature, SGCT account for an estimated 19-29% of corticotroph adenomas131415. The clinicopathological relevance of granulation pattern in corticotroph tumors was unclear until recently.

In multiple studies examining granulation pattern and tumor size, SGCT were statistically larger13,15,16. Hence, we suspect that many of the previously labelled silent corticotroph macroadenomas in the literature were SGCT. The traditional teaching of CD has been “small tumor, big Cushing and big tumor, small Cushing” which reflects the inverse relationship between tumor size and symptomatology17. This observation appears to hold true as Doğanşen et al. found a trend towards longer duration of CD in SGCT of 34 months compared to 26 months in DGCT based on patient history13,17. It has been postulated that the underlying mechanism of the inverse relationship between tumor size and symptomatology is impaired processing of proopiomelanocortin resulting in less effective secretion of ACTH in corticotroph macroadenomas3. Doğanşen et al. also found that the recurrence rate was doubled for SGCT, while Witek et al. showed that SGCT were less likely to achieve remission postoperatively13,16.

Similar to other cases of SGCT, the diagnosis was only arrived retrospective after pathological confirmation10. Interestingly, the characteristic Crooke’s hyaline change of surrounding non-adenomatous pituitary tissue was not observed as one would expect in a state of prolonged glucocorticoid excess in this case. Although classically described, the absence of this finding does not rule out CD. As evident in a recent retrospective study where 10 out of 144 patients with CD did not have Crooke’s hyaline change18. In patients without Crooke’s hyaline change, the authors found a lower remission rate of 44.4% compared to 73.5% in patients with Crooke’s hyaline change. Together with the detectable post-operative ACTH, sparsely granulated pattern and absence of Crooke’s hyaline change in surrounding pituitary tissue, the risk of recurrence is increased. These risk factors emphasize the importance of close monitoring to ensure early detection of recurrence.

Declaration of Interests

☒ The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

☐The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:

Conclusion

We present a case of a sparsely granulated corticotroph macroadenoma presenting with apoplexy leading to remission of hypercortisolism and development of central adrenal insufficiency, hypothyroidism and hypogonadism requiring hormone replacement.

References

Possible Good News! Effects of Tubastatin A on Adrenocorticotropic Hormone Synthesis and Proliferation of Att-20 Corticotroph Tumor Cells

  • Rie HagiwaraDepartment of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, Hirosaki 036-8562, Japan
  • Kazunori KageyamaDepartment of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, Hirosaki 036-8562, Japan
  • Yasumasa IwasakiSuzuka University of Medical Science, Suzuka 510-0293, Japan
  • Kanako NiiokaDepartment of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, Hirosaki 036-8562, Japan
  • Makoto DaimonDepartment of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, Hirosaki 036-8562, Japan
Abstract

Cushing’s disease is an endocrine disorder characterized by hypercortisolism, mainly caused by autonomous production of ACTH from pituitary adenomas. Autonomous ACTH secretion results in excess cortisol production from the adrenal glands, and corticotroph adenoma cells disrupt the normal cortisol feedback mechanism. Pan-histone deacetylase (HDAC) inhibitors inhibit cell proliferation and ACTH production in AtT-20 corticotroph tumor cells. A selective HDAC6 inhibitor has been known to exert antitumor effects and reduce adverse effects related to the inhibition of other HDACs. The current study demonstrated that the potent and selective HDAC6 inhibitor tubastatin A has inhibitory effects on proopiomelanocortin (Pomc) and pituitary tumor-transforming gene 1 (Pttg1) mRNA expression, involved in cell proliferation. The phosphorylated Akt/Akt protein levels were increased after treatment with tubastatin A. Therefore, the proliferation of corticotroph cells may be regulated through the Akt-Pttg1 pathway. Dexamethasone treatment also decreased the Pomc mRNA level. Combined tubastatin A and dexamethasone treatment showed additive effects on the Pomc mRNA level. Thus, tubastatin A may have applications in the treatment of Cushing’s disease.

Access the PDF at https://www.jstage.jst.go.jp/article/endocrj/advpub/0/advpub_EJ21-0778/_pdf/-char/en

 

Pituitary MRI standard and advanced sequences: Role in the diagnosis and characterization of pituitary adenomas

This article involves discussion on the use of standard and advanced magnetic resonance imaging (MRI) sequences to diagnose and characterize pituitary adenomas (PAs), including MRI characteristics related to treatment response that could assist in presurgical assessment and planning, and red flags that could suggest an alternative diagnosis.

  • Besides PAs, several other lesions may be found in the sellar region, such as meningiomas, craniopharyngiomas and aneurysms.
  • For assessing lesions in the sella turcica, sellar MRI is preferred.
  • With a systematic MRI approach to the pituitary region, generally the obtained information comprises: the size and shape of the PA, the presence of cysts or hemorrhage within the tumor, its link with the optic pathways and surrounding structures, potential cavernous sinus invasion, sphenoid sinus pneumatization type, and differential diagnosis with other sellar lesions.
  • In the majority of cases, standard protocol serves the purpose; but additional information could be obtained by using some advanced techniques (susceptibility imaging, diffusion-weighted imaging, 3D T2-weighted high-resolution sequences, magnetic resonance elastography, perfusion-weighted imaging) and such information may be important for some cases.

Severe Infection Including Disseminated Herpes Zoster Triggered by Subclinical Cushing’s Disease

Abstract

Background

Subclinical Cushing’s disease (SCD) is defined by corticotroph adenoma-induced mild hypercortisolism without typical physical features of Cushing’s disease. Infection is an important complication associated with mortality in Cushing’s disease, while no reports on infection in SCD are available. To make clinicians aware of the risk of infection in SCD, we report a case of SCD with disseminated herpes zoster (DHZ) with the mortal outcome.

Case presentation

An 83-year-old Japanese woman was diagnosed with SCD, treated with cabergoline in the outpatient. She was hospitalized for acute pyelonephritis, and her fever gradually resolved with antibiotics. However, herpes zoster appeared on her chest, and the eruptions rapidly spread over the body. She suddenly went into cardiopulmonary arrest and died. Autopsy demonstrated adrenocorticotropic hormone-positive pituitary adenoma, renal abscess, and DHZ.

Conclusions

As immunosuppression caused by SCD may be one of the triggers of severe infection, the patients with SCD should be assessed not only for the metabolic but also for the immunodeficient status.

Read the rest of the article at https://bmcendocrdisord.biomedcentral.com/articles/10.1186/s12902-021-00757-y