Cushing’s syndrome (CS) is often presented due to an adrenocorticotropic hormone (ACTH)-secreting pituitary adenoma, characterized by high chronic cortisol levels. Surgical resection of the pituitary adenoma is the primary treatment, but long-term metabolic and physical sequelae can persist, affecting psychological well-being and social functioning. Glucocorticoids are directly involved in alterations of fat metabolism, favoring centripetal adiposity. Even after hormonal normalization, patients may experience residual lipodystrophy. Impairment of body image may cause psychological distress and social isolation. The objective is to illustrate the potential therapeutic value of reconstructive liposuction in restoring body image and psychological well-being in a patient with persistent lipodystrophy after Cushing’s disease remission.
We report a case of a 16-year-old female with recurrent Cushing’s disease secondary to a pituitary microadenoma, confirmed by elevated urinary free cortisol and magnetic resonance imaging (MRI). It was initially treated with transsphenoidal resection in 2019; disease recurrence was confirmed and again treated in 2024. Despite intervention, the prolonged hypercortisolism developed into secondary lipodystrophy, leading to severe body image dissatisfaction and social withdrawal. Thyroid function remained euthyroid, ruling out metabolic contributors. Because of the psychological distress caused by persistent fat redistribution, the patient underwent elective liposuction in 2025. Postoperative follow-up revealed reduced psychological distress and improved well-being and self-esteem. Reconstructive liposuction can play a key role in the treatment and management of persistent post-CS lipodystrophy, contributing significantly to psychological recovery. Prospective studies evaluating surgical criteria and long-term psychosocial outcomes are needed to define eligibility criteria and assess outcomes, leading to the development of clinical guidelines for aesthetic interventions in post-CS recovery.
Introduction
Corticotroph pituitary adenomas (corticotropinomas) are pituitary tumors that secrete excess adrenocorticotropic hormone (ACTH), causing endogenous Cushing’s syndrome (CS). Most of these adenomas are sporadic and monoclonal, although in some rare cases, they are associated with germline mutations (e.g., in USP8) or genetic syndromes [1,2]. Clinically, excess ACTH causes a classic presentation with centripetal obesity, purple striae, muscle asthenia, hypertension, and emotional disturbances such as depression or anxiety [3-5]. Chronically elevated cortisol levels promote fat deposition in central body regions – face, neck, torso, and abdomen – at the expense of relative thinning of the limbs [3], leading to lipodystrophy that can seriously affect the patient’s quality of life.
At the molecular level, glucocorticoids stimulate the differentiation of preadipocytes into mature adipocytes and enhance lipoprotein lipase activity in peripheral fat tissues [6], thereby increasing the uptake of circulating fatty acids and the storage of triglycerides. At the same time, they increase hepatic lipogenesis and modulate cortisol receptor homeostasis (e.g., 11β-HSD1 in adipose tissue), favoring visceral fat distribution [6]. Although glucocorticoids can induce acute lipolysis, they exert chronic lipogenic effects – especially in subcutaneous adipose tissue – which promotes fat accumulation in the face, neck, and trunk [6]. This central adiposity, characteristic of CS, is further enhanced by increased hepatic lipogenesis and the overexpression of 11β-HSD1 in adipose tissue, which amplifies the local action of cortisol [6].
Case Presentation
In 2019, a 16-year-old female patient was initially diagnosed with a 4 × 3 mm pituitary microadenoma (Figure 1), following clinical suspicion of Cushing’s disease. The diagnosis was confirmed through imaging studies and endocrinological testing, which revealed consistently elevated urinary free cortisol levels ranging from 459 to 740.07 µg/24 hours (normal range: <50 µg/24 hours), indicative of endogenous hypercortisolism. No dynamic load tests (such as dexamethasone suppression or ACTH stimulation) were performed, as the diagnosis was supported by the clinical context and laboratory findings. Moreover, no clinical or biochemical evidence of adrenal insufficiency was observed during follow-up.
Figure 1: T1-weighted sagittal MRI scan showing a corticotroph pituitary microadenoma (4 × 3 mm) circled in red
The lesion is localized within the anterior pituitary gland, consistent with an ACTH-secreting adenoma causing Cushing’s disease in the patient.
MRI, magnetic resonance imaging; ACTH, adrenocorticotropic hormone
The patient underwent transsphenoidal endonasal resection of the pituitary tumor in 2019. Although initially successful, disease recurrence was confirmed, and a second endonasal transsphenoidal surgery was performed in 2024. Despite these interventions, the prolonged hypercortisolism led to the development of secondary lipodystrophy, manifesting as centripetal fat accumulation, a dorsal fat pad, and disproportionate truncal adiposity (Figure 2). These physical alterations had a significant psychosocial impact, as reported by the patient during follow-up visits, resulting in body image dissatisfaction, low self-esteem, and social withdrawal. No formal psychometric scales were administered.
Figure 2: Preoperative and intraoperative images of the patient
A and B panels show the anterior and posterior views prior to liposuction, demonstrating centripetal adipose accumulation characteristic of Cushing’s syndrome. The C panel shows the intraoperative stage following abdominal and flank liposuction, with placement of drainage tubes, and visible reduction in subcutaneous fat volume.
A thyroid function panel revealed a slightly elevated thyroid-stimulating hormone (TSH) level (4.280 μUI/mL; reference range: 0.270-4.200), with total and free T3 and T4 values within normal limits, ruling out clinically significant hypothyroidism as a confounding factor for her phenotype. The biochemical profile suggested a euthyroid state, despite borderline TSH elevation, which was interpreted as a subclinical or adaptive response to chronic cortisol excess (Table 1).
Parameter
Normal Range
Patient’s Value
Cortisol (µg/24 hour)
58.0 – 403.0
459.5 – 740.07
TSH (µUI/mL)
0.270 – 4.200
4.280
Total T3 (ng/mL)
0.80 – 2.00
1.02
Free T3 (pg/mL)
2.00 – 4.40
3.33
Total T4 (µg/dL)
4.50 – 12.00
8.63
Free T4 (ng/dL)
0.92 – 1.68
1.36
Table 1: Comparison between the patient’s hormone levels and standard reference ranges
A persistently elevated 24-hour urinary cortisol range is observed, consistent with endogenous hypercortisolism. The thyroid profile remains within normal limits, with a mildly elevated TSH in the absence of overt thyroid dysfunction. These findings support the functional and metabolic profile characteristic of Cushing’s syndrome.
TSH, thyroid-stimulating hormone
The procedure targeted lipodystrophic regions identified through clinical examination and patient concerns, rather than formal imaging or anthropometric measurements. It aimed to restore body contour, alleviate somatic distress, and improve her overall self-perception and quality of life. Postoperative follow-up revealed patient-reported improvements in body image and psychological well-being. While these outcomes were not evaluated with formal instruments, the clinical improvement was evident and significant from the patient’s perspective, highlighting the role of plastic surgery not only as a reconstructive tool, but also as a therapeutic strategy for restoring dignity and social functioning in patients recovering from CS.
Discussion
After successful treatment of the pituitary adenoma, many metabolic parameters improve; however, fat distribution usually only partially reverses. Longitudinal studies show that, in the medium term, weight and abdominal circumference decrease, and there is some redistribution of fat toward the limbs following cortisol remission [3].
For example, Bavaresco et al. (2024) observed that, after hormone levels normalized, total fat was reduced and part of it shifted from the visceral area to the legs [3]. Nevertheless, their review highlights that a significant proportion of patients continue to present with residual visceral adiposity and moderate obesity (body mass index, or BMI >25), despite hormonal control [7]. In our case, truncal adiposity persisted based on clinical assessment, though no formal anthropometric measurements were performed.
Although liposuction is not traditionally considered first-line therapy for cortisol-induced lipodystrophy secondary to Cushing’s disease, increasing evidence from related lipodystrophic syndromes supports its clinical utility. For instance, in human immunodeficiency virus (HIV)-associated cervicodorsal lipodystrophy, Barton et al. (2021) conducted a 15-year retrospective analysis comparing liposuction and excisional lipectomy, finding that 80% of patients undergoing liposuction alone experienced recurrence, while none of the patients treated with excisional lipectomy showed recurrence – albeit with a higher risk of postoperative seroma formation [7]. These findings underscore that, while liposuction may be less durable than excision, it remains a viable option for selected cases, especially when used for contouring or as an adjunct [7]. Similarly, the Endocrine Society guidelines on lipodystrophy management emphasize the importance of personalized approaches, particularly when localized adipose accumulation contributes to persistent metabolic dysfunction or psychological distress [8]. Akinci et al. (2024) also highlight that, even in partial or atypical lipodystrophy syndromes, patients often report substantial impairment in quality of life due to disfiguring fat redistribution [9]. In this context, liposuction should not be dismissed as merely cosmetic but considered part of a functional and psychosocial rehabilitation strategy. The present case exemplifies this rationale, as the patient – despite biochemical remission of Cushing’s disease – continued to experience debilitating body image disturbances and emotional distress, which were ameliorated following targeted liposuction. This supports the integration of body-contouring procedures into multidisciplinary care protocols for endocrine-related lipodystrophies, especially when residual physical stigma persists after hormonal normalization [7-9].
Body image disorders, such as those secondary to CS or lipodystrophy, significantly impact self-perception, self-esteem, and social functioning. For example, a study by Alcalar et al. (2013) reported that patients with active Cushing’s disease had significantly lower SF-36 scores – particularly in emotional role functioning and mental health domains – compared to controls [10]. Similarly, Akinci et al. (2024) described that patients with partial lipodystrophy demonstrated marked reductions in EQ-5D index values and visual analog scale (VAS) scores, indicating impaired health-related quality of life [9]. These findings underscore that fat redistribution disorders can substantially compromise psychosocial well-being, even after endocrine remission.
This is especially relevant in women, where sociocultural stereotypes surrounding female physical appearance reinforce thinness, symmetry, and youthfulness as standards of personal value and social acceptance [1]. This societal context amplifies body dissatisfaction when visible physical changes occur, even after the clinical remission of endocrine diseases, often leading to social withdrawal, anxiety, or depression [3,10]. Within this framework, plastic surgery – such as reconstructive liposuction – has proven to be a valuable therapeutic tool, offering physical restoration that can enhance self-confidence and promote social reintegration [4]. Postoperative follow-up in our case revealed patient-reported improvements in body image and psychological well-being. While these outcomes were not assessed using formal psychometric tools, the clinical benefit was evident from the patient’s perspective. This aligns with prior findings demonstrating the psychosocial value of reconstructive surgery, which can enhance self-esteem and social reintegration after physical disfigurement [11,12]. These observations underscore the role of plastic surgery not only as a reconstructive intervention, but also as a therapeutic strategy for restoring dignity and quality of life in patients recovering from CS.
Although validated psychometric instruments such as the Body Image Quality of Life Inventory (BIQLI) and the Dysmorphic Concern Questionnaire (DCQ) are available to assess body image disturbances, these were not applied in our case. Nonetheless, they represent useful tools for evaluating subjective impact in both clinical practice and research settings. The BIQLI evaluates the effect of body image on various aspects of life – social interactions, self-worth, sexuality, and emotional well-being – using a Likert scale ranging from -3 (very negative impact) to +3 (very positive impact), providing a quantifiable assessment of its influence on quality of life [5]. The DCQ, on the other hand, identifies dysfunctional concerns about perceived physical flaws by assessing behaviors such as avoidance, mirror checking, and concealment; higher scores are associated with suspected body dysmorphic disorder (BDD) [6]. These tools are useful for initial diagnosis, surgical candidate selection, and postoperative follow-up, as they objectively measure subjective changes related to body image. Their advantages include ease of use, clinical validity, and applicability in research settings. However, they also have limitations: they do not replace comprehensive psychological evaluation, may be influenced by cultural context, and do not detect deeper psychiatric comorbidities. Therefore, a multidisciplinary and ethically grounded approach – integrating plastic surgery, endocrinology, and psychology – is essential to ensure safe and patient-centered treatment planning.
Aesthetic liposuction is associated with significant improvements in perceived body image and patient quality of life [11]. For example, Papadopulos et al. (2019) observed statistically significant increases in perception of one’s own body appearance and high satisfaction with postoperative results [12]. These aesthetic gains were accompanied by psychological improvements: the same study documented an increase in emotional stability and a reduction in postoperative anxiety [12]. Similarly, Kamundi (2023) found that nearly all assessed dimensions of quality of life improved after liposuction (p < 0.05 in most of them). Altogether, these findings suggest that liposuction not only corrects physical alterations typical of CS, but also strengthens self-esteem and psychological well-being by substantially improving satisfaction with one’s body image [11].
Moreover, self-esteem influences adherence to medical treatments and lifestyle changes. By improving self-image through reconstructive surgery, it is plausible that the patient feels more motivated to maintain healthy habits, such as diet and regular exercise, that prevent metabolic relapse [12,13].
Nonetheless, it is important to emphasize that liposuction, in this context, should be viewed as a reconstructive complement, not a primary treatment. There are no established protocols or formal guidelines that explicitly include plastic surgery in the care of cured CS; the decision is personalized, based on the residual functional and psychological impact.
Conclusions
Reconstructive plastic surgery, though not a primary therapeutic approach for CS, plays a key role in enhancing patients’ quality of life following remission. Liposuction, in particular, offers a safe and effective solution for persistent lipodystrophy, providing aesthetic benefits with minimal scarring, rapid recovery, and low complication rates in properly selected patients.
This case underscores the importance of addressing both physical and psychosocial sequelae after endocrine stabilization. A multidisciplinary approach – encompassing endocrinology, neurosurgery, and plastic surgery – not only restores physical appearance but also contributes to emotional recovery, self-esteem, and overall patient satisfaction.
Older age was tied to a higher prevalence of 10 comorbidities among a group of 608 people with Cushing’s disease.
Younger age was associated with most hallmark features of Cushing’s disease.
The presentation of Cushing’s disease varies by age, with older adults having fewer hallmark features of the condition and more comorbidities, according to study findings published in The Journal of Clinical Endocrinology & Metabolism.
Researchers assessed data from 608 people diagnosed with Cushing’s disease and treated with a transsphenoidal tumor resection at 11 academic pituitary centers in the U.S. from 2003 to 2023 (82% women; 77.3% white). Patients were divided into 10-year age interval groups, with the youngest group consisting of those aged 10 to 19 years and the oldest containing adults aged 70 to 79 years. Researchers found Cushing’s disease presents differently as adults age, with older adults experiencing more comorbidities and complications, but fewer hallmark features such as weight gain, facial rounding and hirsutism.
“The diagnosis of Cushing’s disease remains challenging, particularly with age,” Won Kim, MD, associate clinical professor of neurosurgery and radiation oncology at the David Geffen School of Medicine at UCLA, told Healio. “The older a patient is, the more likely that he or she may have a slower-growing tumor with fewer classic manifestations of the disease.”
Kim and colleagues obtained data from the Registry of Adenomas of the Pituitary and Related Disorders. Hallmark features of Cushing’s disease were identified by consensus opinion.
The number of comorbidities increased with patient age (beta = 0.0466; P < .001), according to the researchers.
Older age was associated with several comorbidities for patients with Cushing’s disease, including hypertension (P < .001), diabetes (P < .001), hyperlipidemia (P < .001), cancer (P < .001), coronary artery disease (P < .001), chronic obstructive pulmonary disease (P = .044), cardiac arrhythmia (P = .023), hepatitis (P = .038), anxiety (P = .039) and osteopenia (P = .024). The most common comorbidity was hypertension, which was prevalent in 67.2% of participants.
In an analysis of presenting hallmark features of Cushing’s disease, younger age was positively associated with weight gain (P < .001), facial rounding (P < .001), abdominal striae (P < .001), hirsutism (P < .001), menstrual irregularities (P < .001) and acne (P < .001). Older age was positively tied to obstructive sleep apnea (P = .007). The most common hallmark feature of Cushing’s disease was weight gain, prevalent in 80.2% of patients.
“Our work highlights that we must lower our threshold for suspecting Cushing’s disease in patients without the classic physical manifestations as the age of the patient increases,” Kim said in an interview. “Subtle clues, such as increasingly difficult to control medical conditions such as hypertension and diabetes, may be the only things we see.”
Older age was associated with lower preoperative 24-hour urinary free cortisol levels (beta = –0.0256; P = 6.89 x 10-7), but higher postoperative nadir cortisol (beta = 0.0342; P = 1.03 x 10-4) and higher adrenocorticotropin (beta = 0.0204; P = 5.22 x 10-4).
In an assessment of tumor characteristics, older age was tied to having a higher Knosp grade tumor (beta = 0.011; P = .00435), greater tumor volume (beta = 0.0261; P = .0233) and higher maximum tumor dimension (beta = 0.009; P = 3.82 x 10-4). Older age was inversely associated with Ki-67 index, which is a measure of tumor’s proliferation (beta = –0.0459; P = 1.39 x 10-4).
Age was not associated with a patient’s number of surgical complications. Older age was linked to a greater prevalence of deep vein thrombosis or venous thromboembolism (beta = 0.07; P = .014). Younger age was tied to a higher prevalence of postoperative arginine vasopressin (beta = –0.02; P = .048).
Kim said the study’s findings should encourage health care professionals to adjust their methods for screening for Cushing’s disease in older adults.
“Improving our diagnostic sensitivity through our standardized assessments for the disease should account for these new findings,” Kim told Healio.
Little is known about presenting clinical characteristics, tumor biology, and surgical morbidity of Cushing disease (CD) with aging.
Objective
Using a large multi-institutional data set, we assessed diagnostic and prognostic significance of age in CD through differences in presentation, laboratory results, tumor characteristics, and postoperative outcomes.
Methods
Data from the Registry of Adenomas of the Pituitary and Related Disorders (RAPID) were reviewed for patients with CD treated with transsphenoidal tumor resection at 11 centers between 2003 and 2023. Outcomes assessed included comorbidities, presenting features, preoperative endocrine evaluations, perioperative characteristics, postoperative endocrine laboratory values, and complications.
Results
Of the 608 patients evaluated, 496 (81.6%) were female; median age at surgery was 44 years (range, 10-78 years). Increasing age was associated with increasing comorbidities, frailty, rates of postoperative thromboembolic disease, Knosp grade, tumor size, and postoperative cortisol and adrenocorticotropin nadirs. Conversely, increasing age was associated with decreased hallmark CD features, preoperative 24-hour urinary free cortisol, Ki-67 indices, and arginine vasopressin deficiency. Younger patients presented more frequently with weight gain, facial rounding/plethora, abdominal striae, hirsutism, menstrual irregularities, dorsocervical fat pad, and acne. Obstructive sleep apnea and infections were more common with increasing age.
Conclusion
There are age-dependent differences in clinical presentation, tumor behavior, and postoperative outcomes in patients with CD. Compared to younger patients, older patients present with a less classic phenotype characterized by fewer hallmark features, more medical comorbidities, and larger tumors. Notably, age-related differences suggest a more indolent tumor behavior in older patients, potentially contributing to delayed diagnosis and increased perioperative risk. These findings underscore the need for tailored diagnostic and therapeutic approaches across age groups, with a focus on managing long-term comorbidities and optimizing surgical outcomes.
Activating mutation in Ubiquitin-specific peptidase (USP8) is identified to enhance cell proliferation and adrenocorticotropic hormone (ACTH) secretion from corticotroph pituitary adenoma. We investigated the USP8 variant status in a population of Iranian people with functional corticotroph pituitary adenoma (FCPA). Moreover, a systematic review was conducted to thoroughly explore the role of USP8 variants and the related pathways in corticotroph adenomas, genotype-phenotype correlation in USP8-mutated individuals with FCPA, and the potential role of USP8 and epidermal growth factor receptor (EGFR) as targeted therapies in PFCAs.
Methods
Genetic analysis of 20 tissue samples from 19 patients with PFCAs was performed using Sanger sequencing. Moreover, a systematic literature review was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. PubMed, Scopus, web of Sciences, and Cochrane databases were searched. The last search was performed on 20 September 2023 for all databases.
Results
In our series, we found two somatic mutations including a 7-bp deletion variant: c.2151_2157delCTCCTCC, p. Ser718GlnfsTer3, and a missense variant: c.2159 C > G, p. Pro720Arg (rs672601311) in exon 14. The Systematic review indicated USP8 variant in 35% of corticotroph adenomas, with the highest frequency (25%) in 720 code regions, p. Pro720Arg. Data regarding the impact of USP8 mutational status on clinical characteristics and outcomes in FCPAs are inconsistent. Moreover, Pasireotide as well as inhibitors of EGFR such as Gefitinib and Lapatinib, as well as USP8 inhibitors including -ehtyloxyimino9H-indeno (1, 2-b) pyrazine-2, 3-dicarbonitrile, DUBs-IN-2, and RA-9 indicated promising results in treatment of corticotroph adenomas.
Conclusion
Although the USP8–EGFR system has been identified as the main trigger and target of corticotroph tumorigenesis, more precise multicenter studies are required to yield more consistent information regarding the phenotype-genotype correlation and to develop effective targeted therapies.
Pituitary corticotroph adenoma accounts for 68% of endogenous hypercortisolism [1]. Prolonged exposure to high cortisol levels is associated with a variety of long-term complications, impaired quality of life, and increased mortality [2]. Transsphenoidal surgical excision is the treatment of choice. However, curative surgery is challenging with the initial remission rate of 65–85% and a high recurrence rate [3, 4].
The majority of functional corticotroph adenomas (FCAs) are sporadic. Although the genetic background is not well-established, potential candidate genes are proposed for tumor initiation and progression [5]. Hotspot mutations in ubiquitin-specific peptidase (USP8) are reported in 11–62% of sporadic corticotroph adenomas [6,7,8]. USP8 is a deubiquitinating enzyme that plays an important role in enhancing cell proliferation and regulating cell cycle [9]. The mutant USP8 was found to activate the epidermal growth factor receptor (EGFR) signaling pathway ultimately promoting adrenocorticotrophic hormone (ACTH) secretion [6]. Moreover, overexpression of EGFR and its signaling pathway components in pituitary corticotroph adenoma was reported [10]; and found to be positively associated with ACTH and cortisol levels as well as tumor recurrence [10]. These outcomes suggest that USP8 and EGFR are promising biomarkers for prediction of recurrence and can be used as targeted therapy.
Thus, we conducted a study to examine the USP8 and ubiquitin-specific peptidase 48 (USP48) variations in a group of Iranian people with Cushing’s disease (CD) and carried out a systematic review of the literature regarding the USP8/EGFR and their potential role in the clinical outcomes and targeted therapy in CD.
Methods
Case series
Study population
Paraffin-embedded blocks of pituitary tumor tissue from 19 patients with ACTH-secreting pituitary adenoma who underwent transsphenoidal surgery (TSS) between 2011 and 2019 were examined. The diagnosis of CD was based on clinical features and biochemical criteria [11]. The patients clinically suspected to CD were asked to collect urine free cortisol (UFC) in two separated times and underwent overnight dexamethasone suppression test (ODST). After confirmation of ACTH-dependent Cushing’s syndrome using measurement of ACTH level, a high-dose dexamethasone suppression test (HDDST) was performed to confirm the pituitary source of hypercortisolism. Patients with equivocal results or those with pituitary tumors less than 6 mm in size were undergone inferior petrosal sinus sampling (IPSS). Patient with clinical, biochemical, and radiological evidences of CD were undergone TSS. And eventually, corticotroph adenoma was confirmed using immunohistochemically staining of tumor tissue in all patients. The study was approved by the IUMS Research Ethics Committee (IR.IUMS.REC.1398.082). It was carried out under the declaration of Helsinki and the International Conference on Harmonization of Good Clinical Practice (ICH-GCP) guidelines, and informed consent was obtained from all patients.
DNA extraction and Sanger sequencing
A 10-µm thick section of formalin-fixed and paraffin-embedded (FFPE) tissue per sample was used for genomic DNA extraction. A molecular test was performed by amplification of USP8 and USP48 hotspot exons (exon 14 and exon 10, respectively) using conventional polymerase chain reaction (PCR). USP8 was amplified by two primer pairs; USP8_F1: AGCAGAATACTTTGGAGTGATTTC and USP8_R1: TTTGGAAGGTTCCCTATCCC with 251 bp product, USP8_F2: ACCCCTCCAACTCATAAAGC and USP8_R2: GAGTAGAAACTTTGAAATACAGCAC, with 220 bp product. A 240 bp fragment of USP48 was produced using; USP48_F: CCCGCTAAAGAATAAACAAACTC and USP48_R: GCATTCTAAAACATTTGCCTGC. PCR was done in 25 µl final volume (Ampliqon 2x PCR Mix) containing 0.5 µM of each primer and 30 ng of genomic DNA for 35 cycles (94 °C for 20 s, annealing 60 °C for 20 s and extension 72 °C for 20 s). The quality of PCR products was assessed by 2% agarose gel electrophoresis. Bidirectional Sanger sequencing was performed on an ABI DNA Analyzer (Applied Biosystems), The PCR primers were also used in the sequencing reaction. CodonCode Aligner software was used to analyze hotspot exome sequencing. Sequencing data quality was evaluated using Sanger electropherograms of both forward and reverse strands. The identified somatic mutations were analyzed in DNA taken from whole blood samples, but germline mutation was not detected.
Systematic review
Overview of the systematic literature review
We performed a systematic review of the literature to identify all published papers that reported the frequency of the USP8 variant and the related pathways in corticotroph pituitary adenomas, detailed clinical presentation and outcomes of patients with and without USP8 mutation and examined the USP8 and EGFR as targeted therapy.
Search strategy
We searched the PubMed, Scopus, web of Sciences, and Cochrane databases. The date of the last search was 20 September 2023 for all databases. We did not apply any language restrictions. Search terms included: “Cushing disease”, “Cushing’s disease”, “Corticotroph adenoma”, “Cushing adenoma”, “Client Cushing disease”, “Atypical corticotroph tumor”, “Corticotroph carcinoma”, “Normal pituitary”, “Corticotroph adenoma”, “Corticotroph Tumor”, “Pituitary ACTH Hypersecretion”, “ACTH-Secreting Pituitary Adenoma”, “Mutation”, “Germline mutation”, “Sporadic mutation”, USP8, “ubiquitin specific peptidase 8”, USP48, “ubiquitin specific peptidase 48”, “Epidermal growth factor”, EGF, “Epidermal growth factor receptor” EGFR, Biomarker.
Inclusion and exclusion criteria
All published papers including original articles, case reports, and case series were included in this systematic review provided that they have reported the frequency of USP8 variant or EGFR expression in corticotroph pituitary adenomas, compared the clinical presentation and outcomes of patients with and without USP8 variant, or examined USP8 or EGFR as treatment targets in CD. Studies applying any type of tissue namely resected human pituitary adenoma tissue, primary cell cultures, cell lines, and transfected cells were included. Articles were excluded if they included different types of pituitary tumors and did not separately analyze corticotroph adenomas, or if they were written in any language other than English.
Results
Case series
Baseline characteristics of the participants
This study included 19 patients of whom 63% (n = 12) were women. They aged between 17 and 65 years. Baseline cortisol ranged between 20 and 43 mic/dl. The ACTH level ranged between 34 and 164 pg/ml. The basal UFC ranged between 316 and 1153 mic/24 h. All patients presented with micro-adenoma except for two patients, one man and one woman (supplementary Table 1).
Frequency of USP8 gene variants
Sanger sequencing of 20 CD tumors revealed two heterozygous pathogenic variants in 2 samples: the 7-bp deletion variant, c.2151_2157delCTCCTCC, p. Ser718GlnfsTer3 was found in one patient; another patient showed the missense variant, c.2159 C > G, p. Pro720Arg (rs672601311) in exon 14. The pathogenic variants were found only in tumor tissue. Targeted sequencing (exon 10) of USP48 did not detect any pathogenic variant. The somatic variations in our study are in the catalytic conserved domain of USP8 protein and lead to disruption of the interaction between USP8 catalytic domain and 14-3-3 protein (Fig. 1).
Fig. 1
Sanger sequencing of pathogenic variants in USP8 hotspot exon. (A, B) bi-directional sequencing of heterozygous missense variant, c.2159 C > G, in tissue sample, (C) A Sanger sequencing chromatogram of the blood sample detected no germline c.2159 C > G mutation. (D) Sanger sequencing chromatograms confirm the presence of heterozygous deletion (c.2151_2157delCTCCTCC) in tissue sample of patient II
All patients achieved biochemical and structural cures after surgery except for one man and one woman who suffered from persistent disease because the tumors were not completely resected due to invasion into the cavernous sinus. They underwent radiotherapy after surgery. These two patients did not show the USP8 variant. Moreover, one man without evidence of the USP8 variant and the two women with the USP8 variant presented with recurrence after initial remission. They presented with micro-adenoma before surgery (supplementary Table 1).
Systematic review
The search yielded 1459 initial results. Upon removing the duplications (n = 410), 1049 studies were reviewed based on the relevancy of their titles and abstracts. Having excluded 957 articles, 92 studies were selected for full-text review. After an in-depth review, 31 articles were selected based on the inclusion and exclusion criteria. A PRISMA diagram detailing the search results is shown in Fig. 2.
Fig. 2
Flow diagram of literature search and study selection
In this systematic review we extracted the information regarding the USP8 variant and the EGFR system in corticotroph adenomas. The USP8 variant was found in 460 individuals with FCPA accounting for 35% of the population included in the related published series (Table 1). Moreover, the highest frequency of missense mutation was found in the 720 code region, p.Pro720Arg (25%), followed by 19% in p.Ser718Pro (Fig. 3). In addition, the frequency of frame-shift and in-frame deletion observed in p.Ser718del and p.Ser719del was 12% and 11%, respectively (Fig. 3).
USP8 variants and the related pathways in corticotroph adenomas
In a study of 42 patients with corticotroph adenomas, USP8 variants were as follows: p. P720R (found in five patients), p. S718P (found in two patients), p. P720Q (found in two patients), p. S716Y (found in one patient), and p. S716F (found in one patient) [12]. Another genetic study demonstrated mutated USP8 deubiquitinating EGFR more effectively than wild type USP8. Some variants namely p.S718del, p.718SP, and p.P720R have higher deubiquitinated activity, while others including p.S718C, p.L713R, and p.Y717C showed similar activity compared to the wild type. These variants have been shown to increase the catalytic and proteolytic activity of USP8, which ultimately leads to the activation of the EGFR pathway. High EGFR levels, in turn, stimulate POMC gene transcription and increase plasma ACTH levels [6]. In the study of Seata, the USP8 variant was found in 23% of corticotroph adenomas. The variants were heterozygous, including p.S718, p.P720 (n = 18), p.S719del (n = 10), and p.P720_723 del (n = 1). Moreover, a comparison of 5 USP8 mutant vs. 34 wild-type specimens indicated different gene expression profile. According to the results, 2 genes involving in EGF signaling, CMTM8 (CKLFlike MARVEL transmembrane domain containing 8) and MAPK15 (mitogen-activated protein kinase 15), were upregulated in USP8 variant carriers [13]. Bujko et al. found USP8 mutation in 31.3% of patients with FCA and silent corticotroph adenomas (SCA). In-frame and missense mutations were p.Ser718del (7 patients), p.Pro720Arg (5 patients), p.Ser718Pro (2 patients) and p.Pro720Gln (one patient). USP8-mutated adenomas showed higher level of POMC, CDC25A, MAPK4 but lower level of CCND2, CDK6, CDKN1B than USP8-wild-type tumors [14].
Another study investigated the molecular pathogenesis of the spectrum of corticotroph adenomas, including CD, SCA, CCA (Crooke cell adenomas), and ACTH-producing carcinoma using whole exome sequencing. The patients with ACTH-producing carcinoma showed the highest number of variants in USP8, EGFR, TP53, AURKA, CDKN1A, and HSD3B1 genes. The USP8 variant was found in c.2159 C > G (p.Pro720Arg) and was positively correlated to the tumor size. However, the USP8 variant was not present in any of the patients with CD [15].
Martins and colleagues conducted a study to investigate the USP8 variant and its contribution to gene expression of cell cycle regulators including P27/CDKN1B, CCNE1, CCND1, CDK2, CDK4, and CDK6 in 32 corticotroph adenoma. They identified variants in certain hotspot exons, namely p.720R (found in five patients), p.S718del (found in three patients), p.S718P (found in one patient), and p.S719_T723del (found in one patient). Moreover, there was no difference regarding the gene expression of the cell cycle regulators CDKN1B (P27), CCNE1 (CYCLIN-E1), CCND1 (CYCLIN-D1), CDK2, CDK4, and CDK6 according to USP8 variant status [16]. Another study investigating the USP8 variants and genes involved in cell cycle regulation observed USP variants including p. P720R (n = 8), p.720Q (n = 2), p. S718SP (n = 2), and an in-frame deletion at the 719 position (n = 8). However, USP8-mutated tumors showed lower CDKN1B, CDK6, CCND2 and higher CDC25A expression. They also observed a significantly lower level of p27 in USP8-mutated tumors as compared to the wild-type ones [17].
A comprehensive study determined the presence of EGFR at the protein and mRNA levels in different pituitary adenomas. The highest incidence of EGFR expression was found in corticotroph adenomas. The corticotroph adenomas with EGFR expression did not show p27 immunoreactivity [18].
DNA methylation regulates promoter activities. The study by Araki et al. identified a novel regulatory region in the human POMC gene which functions as a second promoter. Moreover, they indicated that this region is highly methylated in SCAs and highly demethylated in FCAs and ectopic ACTH-secreting tumors. They also demonstrated demethylation of the second promoter is associated with aggressive features of FCAs independent of the USP8 variant or EGFR signaling. In contrast, the first promoter was highly demethylated in USP8-mutated FCAs [19]. Weigand et al. indicated that p27/kip1 protein expression significantly decreased in USP8-mutated adenomas compared to the wild-type USP8 tumors. Moreover, higher expression of heat shock protein 90 (HSP90) and an increase in the phosphorylation of the transcription factor CREB was observed in mutated-USP8 adenomas [20]. Achaete-scute complex homolog 1 (ASCL1) plays an important role in cell proliferation and also regulates POMC in the cell line. In a recent study, genetic analysis of corticotroph adenomas using RNA-seq and IHC showed an increase in ASCL1expression and protein levels in both mutated and wild type USP8 among CD patients [21].
Genotype-phenotype correlation in USP8-mutated individuals with functional corticotroph adenoma
Sanger sequencing of 120 FCPAs indicated the somatic USP8 variant more frequently in women than in men, which was associated with a significant lower size and higher ACTH level. Moreover, compared to the wild-type tumors, the USP8-mutated ones display a higher level of EGFR expression with a higher staining intensity. The initial remission rate and the recurrence rate in patients initially receiving remission were comparable in both groups [7]. Another study of patients with 134 functional and 11 silent corticotroph adenomas demonstrated somatic USP8 variants only in functional adenomas, none of them occurred in silent adenomas. The USP8 variant in adults was associated with lower age, and predominantly occurred in women. Moreover, the presence of USP8 variant was inversely associated with remission [22]. In a cohort of 42 pediatric patients with FCA, five different USP8 variants (three missenses, one frame-shift, and one in-frame deletion) were identified. None of the patients were found to have gremlin USP8 variants. Patients with somatic USP8 variant were significantly older than those with wild-type USP8. However, there was no significant difference in terms of preoperative hormonal profile and tumor invasiveness between the two groups. However, somatic USP8 mutated patients showed a higher rate of recurrence after a mean follow-up of 34.7 months [23].
In a cohort of 48 FCA, patients with the USP8 variant had significantly higher levels of preoperative urine-free cortisol (UFC). But there was no difference in preoperative ACTH and cortisol level between USP8-mutated and wild-type groups. Although initial remission rate was similar in both groups, patients with USP8 variant revealed a significantly higher rate of recurrence within 10 years follow-up, with a significantly shorter time to recurrence [24]. USP8-mutated FCA patients presented with a significantly larger size of adenoma in a retrospective study. But preoperative hormonal profile and the remission rate were similar in both groups [16]. Retrospective genetic analysis of 92 FCA patients indicated that the USP8 variant was significantly higher in women than men. There was no significant difference in preoperative hormonal profile and tumor size between USP8-mutated and wild-type groups. USP8-mutated carriers were more likely to achieve surgical remission. However, after 10 years follow-up, the recurrence rate was similar in the both groups [25]. A Retrospective study of patients with 30 functional and 20 silent corticotroph adenomas showed USP8 variants in 11 and 2 adenomas, respectively. There was no difference in sex, age, preoperative hormonal profile, and size of the adenomas between patients with and without USP8 variants. However, the USP8-mutated tumors revealed a higher rate of invasiveness. Furthermore, somatostatin receptor 5 (SSRT5) was more frequent in USP8-mutated adenomas [26]. In a retrospective study of FCA patients found no difference considering age at the presentation and hormonal profile between patients with and without USP8 variants. However, macro-adenoma was more frequently seen in USP8-mutated patients. Although initial remission rate was similar in the both groups, after a median 5 (2–8) years of follow-up, USP8-mutated carriers were more likely to develop recurrence [27]. The study conducted by Bujko et al., comparing patients with USP8 mutated and wild-type corticotroph adenomas, demonstrated no difference in age, sex, preoperative hormonal profile, tumor invasiveness, proliferation index, and histology (sparsely vs. densely granulation) between the two groups. However, the USP8-mutated patients showed a higher rate of remission [28].
A cohort of Asian-Indian patients with CD identified that there was no significant difference considering age, sex, tumor size, tumor invasion, and preoperative hormonal profile of the participants with and without the USP8 variant. Moreover, the initial remission rate and long-term recurrence, after a mean follow-up of 25.3 ± 13.6 months, were also comparable in both groups [29]. Liu et al. investigated the expression of EGFR and its signaling pathways in FCAs. They demonstrated that EGFR was overexpressed in 29 of 52 patients with FCA. Moreover, the EGFR signal transducing molecules p-EGFR, p-Akt and p-Erk were upregulated in EGFR-overexpressing adenomas but not in EGFR-negative adenomas. Moreover, the expression of EGFR was positively correlated with ACTH and cortisol levels but not with age, sex, or adenoma size. After a mean follow-up of 42.8 months, 22 patients had tumor recurrence. The EGFR expression was positively associated with the recurrence rate [10].
USP8 and EGFR as potential therapeutic targets in functional corticotroph adenoma
Our systematic search yields nine studies investigating the possible role of the USP8 variant in response to the medications. Four studies evaluated the presence of SSTR5 receptors in USP8– mutated tumors. Genetic analysis of FCAs from a cohort of 39 functional and 23 silent corticotroph adenoma indicated that there was no difference regarding the age of the participants, as well as hormonal profile, size, and invasiveness of the tumor between patients with and without USP8 variants. However, USP8-mutated adenomas showed significantly higher SSRT5 expression compared to the wild-type ones [26].
In a cohort study, USP8-mutated FCA patients were dominantly women and showed lower ACTH levels and smaller tumor size, but no difference in cortisol level. Remission rate was significantly higher in USP8-mutated patients compared to the wild-type ones. Moreover, USP8-mutated adenomas were more likely to express SSTR5 [30]. Genetic analysis of 51 FFPE tumors (21 USP8-mutated and 30 wild-type) indicated significantly higher SSTR5 immunoreactivity score in USP8-mutated tumors, regardless of mutation type. Moreover, in vitro study of 24 corticotroph tumors freshly obtained after TSS indicated a significantly better response to Pasireotide treatment, defined as suppression of ACTH secretion, in human corticotroph tumors carrying USP8 variants [31].
A more recent study aimed to investigate the impact of USP8 variants on in vitro response to Pasirotide in primary cultures obtained from 7 FCAs and also in murine corticotroph tumor cells. USP8 variant in both primary cultured cells and AtT20 cells was associated with higher SSTR5 expression. Moreover, this study indicated although associated with SSTR5 upregulation, mutations at the amino acid 718 of USP8 are not associated with a favorable response to pasireotide, whereas USP8 variants at the amino acid 720 might preserve pasireotide responsiveness [32].
Inhibition of EGFR using Gefitinib, a tyrosine kinase inhibitor, in surgically resected human and canine corticotroph cultured tumors suppressed expression of POMC. Moreover, Blocking EGFR activity in mice attenuated POMC expression, inhibited corticotroph tumor cell proliferation, and induced apoptosis [33]. Araki et al. conducted a study to investigate the utility of EGFR as a therapeutic target for CD. EGFR expression was observed by 2.5 months in transgenic (Tg) mice; and aggressive ACTH-secreting pituitary adenomas with features of Crooke’s cells developed by 8 months with 65% penetrance observed. Moreover, they used the EGFR tyrosine kinase inhibitor Gefitinib to confirm reversibility of EGFR effects on ACTH. Gefitinib suppressed tumor POMC expression and downstream EGFR tumor signaling. Plasma ACTH level and pituitary tumor size was significantly lower in Gefitinib group [34].
Another experimental study investigated the effect of Lapatinib, a potent tyrosine kinase inhibitor, on ACTH production and cell proliferation in AtT-20 mouse corticotroph tumor cells. Lapatinib inhibits EGFR. In this study, Lapatinib decreased proopiomelanocortin (POMC) mRNA levels and ACTH levels in AtT-20 cells and also inhibited cell proliferation and induced apoptosis. Inhibition of EGFR signaling contributes to the inhibition of ACTH production and cell proliferation in corticotroph adenomas [35].
The effect of a potent and selective Jak2 inhibitor, SD1029, on ACTH production and proliferation investigated in mouse AtT20 corticotroph tumor cells. They observed that Jak2 inhibitor SD1029 decreased both POMC transcript levels and basal ACTH levels. These in vitro experiments suggest the Jak2 inhibitor suppresses both the autonomic synthesis and release of ACTH in corticotroph tumor cells. SD1029 was also found to inhibit AtT20-cell proliferation. In addition, SD1029 decreased and increased PTTG1 and GADD45β transcript levels, respectively. They seem to contribute, in part, in the Jak2-induced suppression of cell proliferation and ACTH synthesis [36]. An experimental study examined the effect of USP8 inhibitor on EGFR expression level, and cell viability using AtT20 cells treated with 9-ehtyloxyimino9H-indeno (1, 2-b) pyrazine-2,3-dicarbonitrile, a synthesized USP8 inhibitor. This study demonstrated that treatment with USP8 inhibitor, 9‑ehtyloxyimino9H‑indeno(1,2‑b) pyrazine‑2,3 dicarbonitrile, suppresses ACTH secretion, cell viability, and promotes cell apoptosis in AtT20 cells suggesting that USP8 inhibitor could be a new therapeutic candidate for CD [37].
Kageyama et al. investigated the effects of a potent USP8 inhibitor, DUBs-IN-2, on ACTH production and cell proliferation in mouse corticotroph tumor (AtT-20) cells. DUBs-IN-2 decreased Proopiomelanocortin (POMC) mRNA and ACTH levels. Furthermore, DUBs-IN-2 decreased At-20 cell proliferation and induced apoptosis in corticotroph tumor cells [38]. Another study explored the potential effect of the USP8 inhibitor RA-9 on USP8-WT human tumor corticotroph cells and murine AtT-20 cells. RA-9 significantly decreased cell proliferation and increased cell apoptosis in AtT-20 cells. Moreover, RA-9 reduced ACTH release by USP8-mutant cells. The combined treatment with RA-9 and pasireotide resulted in more efficient in inhibiting ACTH secretion compared with RA-9 or pasireotide alone. Furthermore, similar to pasireotide, RA-9 was able to significantly reduce phospho- ERK1/2 levels in both AtT-20 cells and primary cultured cells from corticotropinomas [39].
Another study, investigating the USP8 variants and genes involved in cell cycle regulation, looked for the role of USP8 variants or a changed p27 level in the response to Palbociclib, Flavopiridol, and Roscovitine, in vitro, using murine corticotroph AtT-20/D16v-F2 cells. They did not found any significant difference in cell viability or cell proliferation between the AtT-20/D16v-F2 cells overexpressing wild-type and mutated USP8 that were treated with cell cycle inhibitors. There was also no difference in the response to inhibitors of CKDs in the cells with overexpression of p27 and control cells [17].
Analytical conclusion
In our series, we found two USP8 variants including a 7-bp deletion variant, c.2151_2157delCTCCTCC, p. Ser718GlnfsTer3, and a missense variant, c.2159 C > G, p. Pro720Arg (rs672601311) in exon 14. Moreover, the systematic review of the published data indicated that 35% of corticotroph adenomas harbor USP8 variant the most of which was found in the 720 code region, p. Pro720Arg. Similar to the most previous studies, the USP-8 mutated patients were women, presented with micro-adenoma and experienced recurrence after initial remission.
We systematically reviewed the literature regarding the USP8 variant in corticotroph adenomas and classified the results into three categories; including USP8 variants and the related pathways, genotype-phenotype correlation in USP8-mutated individuals, and USP8 and EGFR as potential therapeutic targets.
Different USP8 variants are identified in corticotroph adenomas. Activation of the EGFR pathway is a well-established consequence of USP8 variants [6, 15]. But there is inconsistency regarding the role of USP8 variants in cell cycle regulation in corticotroph adenomas. Some studies showed no difference in the gene expression of the cell cycle regulators CDKN1B (P27), CCNE1 (CYCLIN-E1), CCND1 (CYCLIN-D1), CDK2, CDK4, and CDK6 according to USP8 variant status [21]; while the others indicated USP8-mutated tumors have lower CDKN1B, CDK6, CCND2 and higher CDC25A expression [20]. Moreover, demethylation of the first promoter is affected with USP8 variant status [19]. However, more studies are required to establish the pathway underlying the USP8 variants.
Data regarding sex, age, hormonal level, tumor size, and clinical outcomes in USP8-mutated individuals with FCA are relatively consistent among different studies. The USP8 variant seems to be associated with younger age and is more likely to occur in women. Meta-analysis of data from ten series indicated USP8 variant is 2.63 times higher in women than in men [40]. Since CD is more prevalent in young women, the potential effect of estrogen on the growth of USP8-mutant corticotroph cells has been hypothesized. There is evidence that corticotroph cells express estrogen receptors [41]. Moreover, in vitro studies indicated estrogen can stimulate corticotroph cell proliferation mediated by EGFR signaling pathways [42]. More precise studies are required to better explain the age-sex distribution of USP8 variant in patients with CD.
Results regarding the hormonal pattern among the series are partly controversial. Two series indicated significantly higher levels of ACTH and UFC in USP8-mutated patients compared to the wild-type ones [7, 24]. Moreover, one study demonstrated the expression levels of EGFR were positively correlated with ACTH and cortisol levels [10]. Conversely, one study showed a significantly lower ACTH level in patients with the USP8 variant [30]. However, in a systematic analysis of the two series the correlation of UFC and USP8 variant did not reach a significant difference, this might be due to the small number of cases included in the analysis [40].
There are also some discrepancies on tumor size and invasiveness in USP8-mutated tumors. Some studies indicated a significant smaller size in USP8-mutated tumors, while others showed a significant larger size in USP8-mutated tumors. But some study found no significant difference regarding tumor size and invasiveness between USP8-mutated and wild-type tumors. A recent systematic analysis of magnetic resonance imaging (MRI) findings from individuals with CD indicated USP8-mutated tumors are more likely to be less than 10 mm compared to wild-type ones [40]. Moreover, a cohort of 60 patients with FCA indicated smaller tumor size and less invasiveness in USP8-mutated tumors [30]. In contrast to these findings, a cohort of Brazilian patients observed a tendency toward more somatic USP8 variant in tumors more than 10 mm in size [40]. These discrepancies might be due to the different methods used for extraction of MRI data.
Considering the clinical outcomes, most studies indicated a higher remission rate except for one that showed a significantly lower rate of remission in USP8-mutated patients [22, 25, 28, 30]. Moreover, some studies demonstrated a higher rate of recurrence in carriers of USP8 variant [24, 27, 42]. However, other studies found no significant difference neither in the initial remission nor in the late recurrence rate between the carriers of USP8 variant and the individuals with wild-type USP8. The inconsistency in the results might be due to the lack of a systematic protocol for evaluation of these patients. Moreover, the number of patients included in the different studies was relatively low. Further multicenter prospective studies with the same protocol are required to yield more consistent information regarding the influence of USP8 variant on the clinical presentation as well as early and late outcomes of FCAs.
There are promising studies regarding USP8-targeted therapy. We found evidence that USP8-mutated tumors have higher SSRT5 expression [30, 31]. Moreover, in vitro studies demonstrated that Pasirotide suppressed ACTH secretion significantly more in the USP8-mutated tumors than in wild-type ones [31]. These evidences suggest that USP8 mutational status could be used as a marker of Pasirotide response in CD. Furthermore, USP8-mutated tumors are more likely to express EGFRs compared to the wild-type ones [6]. Inhibition of EGFR using Gefitinib and Lapatinib has been associated with promising results regarding the EGFR-targeting therapy in CD [33,34,35]. Moreover, experimental studies of two USP8 inhibitors, 9‑ehtyloxyimino9H‑indeno (1,2‑b) pyrazine‑2,3 dicarbonitrile and DUBs-IN-2, have shown their potential to suppress POMC expression and ACTH secretion, decrease cell proliferation, and promote apoptosis [37, 38].
In summary, the studies investigated the association of USP8– variants and clinical manifestations as well as clinical outcomes of the corticotroph adenomas are partly inconsistent. More precise multicenter studies are required to yield more consistent information regarding the phenotype-genotype correlation and to develop effective targeted therapies.
Data availability
The datasets used and/or analyzed during the current atudy are available from the corresponding author on reasonable request.
Abbreviations
ABI:
Applied Biosystems
ACTH:
Adrenocorticotropic Hormone
CCA:
Crooke Cell Adenomas
CD:
Cushing’s Disease
DNA:
Deoxyribonucleic Acid
EGFR:
Epidermal Growth Factor Receptor
Erk:
Extracellular Signal-Regulated Kinases
FCAs:
Functional Corticotroph Adenomas
FCPA:
Functional Corticotroph Pituitary Adenoma
FFPE:
Formalin-Fixed And Paraffin-Embedded
ICH-GCP:
International Conference On Harmonization Of Good Clinical Practice
IHC:
Immunohistochemistry
MRI:
Magnetic Resonance Imaging
PCR:
Polymerase Chain Reaction
PRISMA:
Preferred Reporting Items For Systematic Reviews And Meta-Analyses
RNA-seq:
RNA Sequencing
SCA:
Silent Corticotroph Adenomas
TSS:
Transsphenoidal Surgery
USP8:
Ubiquitin-Specific Peptidase
USP48:
Ubiquitin Specific Peptidase 48
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We thank all the participants enrolled in this study.
Funding
The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by the Iran University of Medical Sciences No. IR.IUMS.REC.1398.082.
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Author notes
Nahid Hashemi-Madani and Sara Cheraghi are joint first authors.
Authors and Affiliations
Endocrine Research Center, Institute of Endocrinology and Metabolism, Iran University of Medical Sciences, Tehran, Iran, No. 10, Firoozeh St., Vali-asr Ave., Vali-asr Sq, Tehran, Iran
Nahid Hashemi-Madani, Sara Cheraghi, Zahra Emami & Mohammad E. Khamseh
Department of Pathology, Firoozgar hospital, Iran University of Medical Sciences, Tehran, Iran
Ali Zare Mehrjardi
Department of Endocrinology, Arad Hospital, Tehran, Iran
Mahmoud Reza Kaynama
Contributions
Conception and design: NHM and MEK; Development of methodology: NHM, SC and ZE; Acquisition, analysis, and interpretation of data: NHM, SC, ZE and AZM; Writing, review, and/or revision of the manuscript: NHM, SC, ZE, MRK and MEK; Administrative, technical or, material support: NHM, MEK; Study supervision: MEK; All authors read and approved the final manuscript.
This study was performed in accordance with the 1964 Helsinki Declaration, and was approved by the Ethics Committee of Iran University of Medical Sciences. Informed consent was obtained from all individual participants included in the study.
Consent for publication
Not applicable.
Competing interests
The authors declare no competing interests.
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Additional file 1 of Targeted analysis of Ubiquitin-Specific Peptidase (USP8) in a population of Iranian people with Cushing’s disease and a systematic review of the literature
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Hashemi-Madani, N., Cheraghi, S., Emami, Z. et al. Targeted analysis of Ubiquitin-Specific Peptidase (USP8) in a population of Iranian people with Cushing’s disease and a systematic review of the literature. BMC Endocr Disord24, 86 (2024). https://doi.org/10.1186/s12902-024-01619-z
Spontaneous remission of Cushing’s disease (CD) is uncommon and often attributed to pituitary tumor apoplexy. We present a case involving a 14-year-old female who exhibited clinical features of Cushing’s syndrome. Initial diagnostic tests indicated CD: elevated 24h urinary cortisol (235 µg/24h, n < 90 µg/24h), abnormal 1 mg dexamethasone overnight test (cortisol after 1 mg dex 3.4 µg/dL, n < 1.8 µg/dL), and elevated adrenocorticotropic hormone concentrations (83.5 pg/mL, n 10-60 pg/mL). A pituitary adenoma was suspected, so a nuclear MRI was performed, with findings suggestive of a pituitary microadenoma. The patient was referred for a transsphenoidal resection of the microadenoma. While waiting for surgery, the patient presented to the emergency department with a headache and clinical signs of meningism. A computed axial tomography of the central nervous system was performed, and no structural alterations were found. The symptoms subsided with analgesia. One month later, she presented again to the emergency department with clinical findings of acute adrenal insufficiency (cortisol level of 4.06 µg/dL), and she was noted to have spontaneous biochemical remission associated with the resolution of her symptoms of hypercortisolism. For that reason, spontaneous CD remission induced by pituitary apoplexy (PA) was diagnosed. The patient has been managed conservatively since the diagnosis and remains in clinical and biochemical remission until the present time, after 10 months of follow-up. There are three unique aspects of our case: the early age of onset of symptoms, the spontaneous remission of CD due to PA, which has been rarely reported in the medical literature, and the fact that the patient presented a microadenoma because there are fewer than 10 clinical case reports of PA associated with microadenoma.
Introduction
Cushing’s disease (CD) is characterized by excessive production of adrenocorticotropic hormone by a pituitary adenoma and represents the most common cause of endogenous Cushing’s syndrome (CS) [1]. CD was first reported in 1912 by Harvey Williams Cushing, and he described 12 cases at the Peter Bent Brigham Hospital in Baltimore [2]. This disease has a global incidence of approximately 2.2 cases per 1,000,000 people and occurs more frequently in women from 20 to 50 years of age [3]. Pituitary apoplexy (PA) is a rare condition that occurs in 2-12% of cases, and it has a high morbidity and mortality rate [4]. We report an interesting case of a woman diagnosed with CD who achieved spontaneous remission of her disease after a PA.
Case Presentation
A 14-year-old female presented with a two-year history of weight gain (32 kg), depression, elevated blood pressure, type 2 diabetes mellitus, and growth failure (height less than the third percentile). Her height was 140 cm, and her BMI was 28.1 (97th percentile). At presentation, she had not yet reached menarche. Physical examination revealed Tanner 2 breast development, acne, hirsutism, moon facies, dorsocervical fat pad, central obesity, and stretch marks. Initial laboratory tests showed hemoglobin A1C of 13%, low-density lipoprotein of 167 mg/dL, triglycerides of 344 mg/dL, high-density lipoprotein of 26 mg/dL, creatinine of 0.4 mg/dL, and elevated liver enzymes. Abdominal ultrasound indicated moderate hepatic steatosis changes.
Given the high suspicion of CS, a hormonal profile was conducted (Table 1), confirming CS and subsequently diagnosing CD. A nuclear MRI revealed a 2.6 × 1.8 mm pituitary lesion (Figure 1), prompting referral for transsphenoidal resection of the pituitary microadenoma.
Laboratories
Reference range
Initial
One month
Three months
Six months
TSH (mUI/L)
0.35-4.94
–
2.17
–
2.01
AM cortisol (µg/dL)
6.02-18.4
17.3
4.06
<0.5
4.7
1 mg DST (µg/dL)
<1.8
3.4
–
–
–
8 mg DST (µg/dL)
<50% suppression
1.9 (78% suppression)
–
–
–
Urine-free cortisol (µg/24h)
<90
235
–
–
–
ACTH (pg/mL)
10-60
83.5
–
19.2
9.7
IGF-1 (ng/mL)
36-300
–
–
–
293
Table 1: Pertinent laboratory investigation at baseline and follow-up with our patient
Figure 1: Axial view of a T1 MRI with contrast showing a sellar lesion
The red arrow shows a microadenoma in relation to the normal pituitary gland.
Approximately one month after the suppression tests and while awaiting surgery, the patient presented to the emergency department with a sudden, severe, holocranial headache accompanied by projectile vomiting and diplopia, suggestive of meningism. A computed axial tomography of the central nervous system was conducted, revealing no structural abnormalities. Symptoms resolved with intravenous analgesia within approximately four to six hours. Subsequently, the patient experienced a significant decrease in insulin requirements, ultimately leading to the suspension of insulin therapy due to persistent hypoglycemia.
Weeks after the headache episode, the patient was reevaluated in the emergency department with a three-day history of diffuse abdominal pain, vomiting, asthenia, myalgia, hypotension, tachycardia, orthostatism, and recurrent hypoglycemia despite insulin suspension. Acute adrenal insufficiency was suspected and confirmed by a cortisol level of 4.06 µg/dL. Treatment with intravenous hydrocortisone 50 mg every six hours was initiated, leading to complete resolution of symptoms within 72 hours. The patient was discharged on maintenance therapy with oral hydrocortisone (20 mg in the morning and 10 mg at night). Subsequent follow-ups showed undetectable cortisol levels. Currently, the patient has been followed up for 10 months post-event, showing persistent clinical and hormonal remission of her disease.
Discussion
CD represents approximately 80% of cases of endogenous hypercortisolism, and pituitary microadenomas are the most common cause of CD in all age groups [5]. CD prevalence is 0.3-6.2 cases per 100,000 people [3], which represents 4.4% of all pituitary adenomas [6], and it is up to five times more likely to occur in women than men. Spontaneous remission of CD is rare, and it is mainly due to the apoplexy of a pituitary tumor [7].
PA is a potentially fatal condition resulting from hemorrhage or necrosis of a pituitary adenoma that produces compression of the surrounding structures with symptoms that can be critical and even fatal [8]. PA affects between 2% and 12% of patients with pituitary adenomas, mainly in nonfunctional macroadenomas [9]. Although the main mechanism of PA is hemorrhage, it can also be due to a hemorrhagic infarction or an infarction without hemorrhage; this last scenario is clinically less aggressive [10]. Among the most important precipitating factors are craniocerebral trauma, pregnancy, thrombocytopenia, coagulopathies, pituitary stimulation tests, drugs such as anticoagulants and estrogens, surgeries that are complicated by hypotension, and radiotherapy [4,11,12].
There are three unique aspects of our case. First, the age of onset is 14 years old. This characteristic has been reported in less than 6% of cases of CD, with a mean age of onset between 12.3 and 14.1 years and a slightly higher incidence in men (63%) [13]. In this population, CD is the most common cause of hypercortisolism, accounting for 75-80% of all cases [14]. Furthermore, our patient presented a significant weight gain, severe compromise in her height, hypertension, depression, and diabetes mellitus, which is compatible with the classic profile described for CD in pediatric ages. It is important to clarify that although type 2 diabetes mellitus is common in adults, it is unusual in the pediatric population [13].
Second, spontaneous remission in CD due to apoplexy has been rarely reported in the past; hence, our case is an important addition to the scant literature on this unusual phenomenon. Although there are characteristics suggestive of PA, such as hyperdense lesions within the pituitary gland and the reinforcing ring, a CT scan has a low sensitivity for detecting pituitary hemorrhage (21-46%); therefore, a negative CT scan does not rule out PA in cases where there is infarction without hemorrhage, a situation that could correspond to our case [15].
The third unique feature of our case is that the stroke occurred in the context of a microadenoma, a situation reported in less than 10 cases in the literature. Despite being a microadenoma, the symptoms of PA were severe, with symptoms of meningism, an intense headache, vomiting, and the development of adrenal insufficiency. Taylor et al. [16] reported a similar case of a 41-year-old female with microadenoma whose PA was associated with severe headache and vomiting.
The main differential diagnosis in our case is cyclical CS (CCS), a disorder that occurs in 15% of CS cases, especially in CD [17]. The diagnosis of CCS is classically established with three peaks and two valleys in cortisol secretion, spontaneous fluctuations, and clinical features of CS [7]. The possibility of CCS was ruled out due to the typical presentation of the PA event and the persistence of hypocortisolism.
Finally, several cases of recurrence of their disease have been described after remission of CS due to AP. Those recurrences usually develop in follow-ups of up to seven years [18]. At the time of the last evaluation (10 months post-PA), the patient remained in remission, but long-term follow-up is required to detect both reactivation and hypopituitarism [19].
Conclusions
CD is a rare entity in the pediatric population, usually associated with a pituitary microadenoma. Spontaneous remission of this disease is very uncommon, but when it occurs, it is mainly due to PA. We describe a case with three unique aspects: CD with an early age of onset of symptoms, spontaneous remission of CD due to PA, which has been rarely reported in the medical literature, and the fact that there are less than 10 clinical case reports of PA associated with microadenoma. It is imperative for clinicians to be aware of this possible outcome in patients with CD.
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