Chief Cushie ~MaryO~ Posted February 22 Chief Cushie Report Share Posted February 22 Highlights EAS should be considered in patients presenting with rapid progression of ACTH-dependent hypercortisolism causing severe clinical and metabolic abnormalities. Ectopic ACTH secretion by a pheochromocytoma should be suspected in cases of ACTH-dependent Cushing syndrome in the presence of an adrenal mass. If required, medical management with steroidogenesis inhibitors can be initiated at the time of EAS diagnosis to control clinical and metabolic derangements associated with severe hypercortisolemia In patients with ACTH-dependent Cushing syndrome from an ectopic source, inhibiting steroidogenesis should be reserved for cases where the initial diagnosis is unclear or patients who are not suitable candidates for surgery. Unilateral adrenalectomy is indicated in the management of ACTH/CRH-secreting pheochromocytomas and is typically curative. Catecholamine blockade should be started prior to surgical removal of catecholamines-secreting pheochromocytomas. A multidisciplinary approach is required to diagnose and manage this condition. Abstract Background/Objective Ectopic co-secretion of corticotropin-releasing hormone (CRH) and adrenocorticotropic hormone (ACTH) in silent (i.e., noncatecholamine-secreting) pheochromocytoma is a rare cause of Cushing Syndrome (CS). Case Report A 57-year-old woman rapidly developed hypercortisolism, clinically manifesting as fatigue, muscle weakness, weight gain, and worsening hypertension, and biochemically characterized by hypokalemia and marked elevation of serum cortisol and plasma ACTH. This acute presentation suggested a diagnosis of ectopic ACTH syndrome (EAS). Imaging studies revealed a right adrenal mass that enhanced after administration of the radioisotope 68Ga-DOTATATE. Plasma metanephrines were normal in two separate measurements. The possibility of a silent pheochromocytoma was considered. After controlling her hypercortisolism with metyrapone and surgical preparation with alpha blockade, the patient underwent elective right adrenalectomy. Pathology revealed a pheochromocytoma that stained focally for ACTH and CRH. Postoperatively, cortisol levels normalized, the hypothalamic–pituitary–adrenal (HPA) axis was not suppressed, and clinical symptoms from hypercortisolism abated. Discussion Patients who exhibit a rapid progression of ACTH-dependent hypercortisolism should be screened for ectopic ACTH syndrome (EAS). The use of functional imaging radioisotopes (such as gallium DOTA-peptides), improves the detection of ACTH-secreting tumors. Preoperative treatment with steroidogenesis inhibitors helps control clinical and metabolic derangements associated with severe hypercortisolemia, while alpha blockade prevents the onset of an adrenergic crisis. Conclusion We present a rare case of EAS due to a silent pheochromocytoma that co-secreted ACTH and CRH. Pheochromocytoma should be considered in patients with EAS who have an adrenal mass even in the absence of excessive catecholamine secretion. Key words ectopic ACTH syndrome Cushing Syndrome non-catecholamine-secreting pheochromocytoma Abbreviations EAS ectopic ACTH syndrome CS Cushing Syndrome CRH corticotropin-releasing hormone ACTH adrenocorticotropic hormone DHEA-S dehydroepiandrosterone sulfate UFC urine free cortisol PRA plasma renin activity Introduction Cushing Syndrome (CS) is rare, with an estimated incidence of 0.2-5.0 per million people per year, and prevalence of 39-79 per million (1). Ectopic ACTH Syndrome (EAS), a type of CS originating from extra-pituitary ACTH-secreting tumors, is uncommon. The prevalence of CS due to ACTH-secreting adrenal medullary lesions is not well established. However, EAS is observed in approximately 1.3% of all identified cases of pheochromocytoma (2). Recognizing EAS can be challenging due to its rarity, leading to delayed diagnosis. Neuroendocrine neoplasms can produce CRH, which can lead to the secretion of ACTH by the pituitary. In certain cases, co-secretion of ACTH and CRH by an adrenal neoplasm has been observed. Only two published cases have provided definitive biochemical and immunohistochemical evidence of exclusive CRH secretion (3). Case Report A 57-year-old woman with a history of well-controlled hypertension sought care due to a two-month history of 60 lb weight gain, facial rounding, easy bruising, muscle weakness, lower extremity edema and acne. Her blood pressure control had worsened, and laboratory tests showed a markedly low serum potassium level of 1.8 mmol/L while taking hydrochlorothiazide. To manage her blood pressure, she was prescribed a calcium channel blocker, an angiotensin receptor blocker, and potassium supplements. However, her symptoms worsened, and she was referred to our emergency department. Blood pressure at presentation to our hospital was 176/86 mmHg. She had characteristic features of CS, including face rounding, supraclavicular fullness, dorsocervical fat accumulation, pedal edema, oral candidiasis, multiple forearm ecchymoses, and acneiform skin eruptions. No visible abdominal striae were present. She had no family history of pheochromocytoma, or multiple endocrine neoplasia type 2. Serum cortisol level was 128 mcg/dL (normal range: 4.6-23.4) at 5 PM, with an ACTH level of 1055 pg/mL (normal range: 6-50); serum DHEA-S level was elevated at 445 mcg/dL (normal range: 8-188). Her 24-hour urine cortisol was at 12,566 mcg (normal range: 4.0-50.0). Plasma metanephrines were normal at <25 pg/mL (normal range: <57), and plasma normetanephrine was 44 (normal range: <148). A second plasma metanephrine measurement showed similar results. Serum aldosterone level and plasma renin activity were low at 2 ng/dL (normal range: 3-16) and 0.11 ng/mL/h (normal range: 0.25-5.82), respectively. Dopamine and methoxytyramine levels were not measured. An abdominal CT revealed a 4.8 x 4.5 x 5 cm right heterogeneously enhancing adrenal mass with a mean Hounsfield Unit of 68 in the non-contrast phase, and an absolute percentage washout of 30% (Fig 1A). The left adrenal gland appeared hyperplastic (Fig 1B). An Octreoscan, which was the in-hospital available nuclear medicine imaging modality, confirmed a 5.1 cm adrenal mass that was mild to moderately avid, with diffuse bilateral thickening of the adrenal glands and no other focal radiotracer avidity. A pituitary MRI did not show an adenoma, and EAS was suspected. Further evaluation with 68Ga-DOTATATE PET/CT (Fig 2) performed after her admission demonstrated an avid right adrenal mass consistent with a somatostatin receptor-positive lesion. No other suspicious tracer uptake was detected. These findings were consistent with a neuroendocrine tumor, such as pheochromocytoma. Download : Download high-res image (261KB) Download : Download full-size image Fig. 1. Preoperative abdominal computed tomography scan showing a 4.8 x 4.5 x 5 cm right heterogeneously enhancing adrenal mass with irregular borders (A) and a hyperplastic left adrenal gland (B). Download : Download high-res image (219KB) Download : Download full-size image Fig 2. 68Ga-DOTATATE PET/CT showing an avid right adrenal mass. To control her symptoms while undergoing workup, the patient received oral metyrapone 500 mg thrice daily and oral ketoconazole 200 mg twice daily. Ketoconazole was stopped due to an increase in transaminases. The dosage of metyrapone was increased to 500 mg four times daily and later decreased to alternating doses of 250 mg and 500 mg four times daily. Within 3 weeks of starting medical therapy, serum cortisol level normalized at 20 mcg/dL. The 24-hour UFC improved to 246.3 mcg/24h. She experienced gradual improvement in facial fullness, acne, and blood pressure control. The possibility of a silent pheochromocytoma was considered, and a-adrenergic blockade with doxazosin 1 mg daily was started 1 month prior surgery. She underwent surgery after two months of metyrapone therapy. With an unclear diagnosis and a large, heterogeneous adrenal mass, the surgical team elected to perform open adrenalectomy for en bloc resection due to concerns for an adrenal malignancy. The tumor was well-demarcated and did not invade surrounding structures (Figure 3A). H&E-stained sections showed classic morphologic features of a pheochromocytoma (Figure 3B), with immunohistochemistry demonstrating strong immunoreactivity for synaptophysin and chromogranin, and negative SF- I and inhibin stains excluding an adrenal cortical lesion. The sections analyzed by QuPath (4) revealed that approximately 4% of ce11s were ACTH cells, often found in isolation, and had a clear, high signal-to-noise staining (Figure 3C). CRH cells were less prevalent, comprising about 2.4% of the total analyzed cells, and tended to cluster together (Figure 3D). These cells had more background staining, resulting in a lower signal- to-noise ratio. Download : Download high-res image (663KB) Download : Download full-size image Figure 3. Gross and Histopathological analysis of the patient’s pheochromocytoma. (A) Image of the gross excised specimen. (B) H&E staining (200x final magnification) demonstrates prominent vascularity and cells with finely granular, eosinophilic cytoplasm and salt-and-pepper chromatin. (C) ACTH staining (200x final magnification) shows clear and isolated positive cells, representing about 4.0% of the section analyzed by QuPath. (D) CRH staining (200x final magnification) reveals tight clusters of positive cells, accounting for 2.4% of the total cells. Positive (human placenta and hypothalamus) and negative (thyroid gland) control tissues performed as expected (data not shown). The patient's postoperative recovery was uneventful, with a short course of hydrocortisone which was stopped 1 week after surgery after HPA axis evaluation showed normal results. After one month, hypercortisolism had resolved, as shown by a normal 24-hour UFC at 28 mcg. Administration of dexamethasone at 11 PM resulted in suppression of morning cortisol to 0.8 and 0.6 mcg/dL 1 and 7 months after surgery, respectively. Her liver function tests normalized, and blood pressure was well-controlled with amlodipine 10 mg daily and losartan 100 mg daily. Genetic testing for pheochromocytoma predisposition syndromes is currently planned. Discussion EAS accounts for 10-20% of cases of ACTH-dependent CS (5). This condition can be caused by several neuroendocrine neoplasms that produce bioactive ACTH (6) In the literature, we have found 99 documented cases of EAS caused by a pheochromocytoma. Of these, 93% showed ACTH expression. Only two cases have been reported with dual staining of ACTH and CRH (7). Exclusive CRH production has only been reported in two cases (8:9). However, the true prevalence of CRH-producing pheochromocytomas might be underestimated, as most cases testing for CRH expression was not performed. Although the clinical presentation of EAS may be highly variable, there is often a rapid onset of hypercortisolism accompanied by severe catabolic symptoms. The diagnostic process should focus on identifying the location of a potential neuroendocrine neoplasm responsible for the ACTH secretion. Sometimes the peripheral origin of ACTH must be confirmed by inferior petrosal sinus sampling (IPSS). In this case, given the clinical presentation consistent with EAS, negative pituitary MRI, and the presence of an adrenal mass that needed to be removed independently, IPSS was not performed. Neuroendocrine neoplasms express somatostatin receptors on their surface, which allow functional imaging using [11 lln]-pentetreotide (Octreoscan). However, Octreoscan has a low sensitivity in detecting occult EAS. In cases where the tumor is in the abdomen and pelvis, Octreoscan has limited utility in locating the source of ACTH (10). This increased risk of false negatives is caused by physiological tracer uptake by the liver, spleen, urinary tract, bowel, and gallbladder. The use of Gallium-68 labeled somatostatin receptor ligands (PET/CT 68Ga-DOTATATE) is more effective in detecting somatostatin receptors (SSTR2) than [11lln]-pentetreotide due to its higher spatial resolution and affinity (11)_ This test was performed after discharge form the hospital to rule out the presence of a second, smaller neuroendocrine tumor that the Octreoscan might have missed. A new molecular imaging technique targeting CRH receptors (68Ga CRH PET/CT) has shown potential in identifying tumors expressing CRH, but its availability remains limited (12). In our patient's case, both the Octreoscan and 68Ga- DOTATATE successfully identified the adrenal tumor as a potential ACTH/CRH secretion source. According to relevant guidelines, presurgical adrenergic blockade is recommended for patients with biochemical evidence of catecholamine excess (13, 14). Conversely, silent pheochromocytomas can generally be operated without alpha blockade (15). Despite this, we opted to administer pre-operative alpha blockade as a precautionary measure for this patient. Pathology examination confirmed the diagnosis of pheochromocytoma. ACTH and CRH staining demonstrated that clear and significant populations of two separate ACTH and CRH positive cells were present in the excised pheochromocytoma. ACTH/CRH cells were dispersed throughout various regions of the pheochromocytoma rather than being well-defined, separate histological entities. As a result, there is no indication that this resulted from collision tumors, but rather random mutation and expansion of tumor cells into ACTH or CRH secreting cells. These results have limitations, including variation in ACTH and CRH expressing regions due to tumor heterogeneity, nonspecific binding of polyclonal antibodies, and normal low-rate false negative/positive detection using QuPath. Post-surgical normal HPA activity was likely due to the de-suppression of the HPA axis by medical therapy, but it may also be explained by chronic stimulation of corticotroph cells induced by ectopic CRH secretion. The standard approach to managing EAS involves surgical intervention. However, surgery may not be a viable option in cases where the source of ACTH production is unknown. Medical therapy to reduce or block excess cortisol can be used in such circumstances. Conclusions In conclusion, a pheochromocytoma causing EAS should be considered even in the absence of elevated plasma metanephrines. These tumors may simultaneously express ACTH and CRH.CRH. References 1 C. Steffensen, A.M. Bak, K. Zøylner Rubeck, J.O.L. Jørgensen Epidemiology of Cushing’s syndrome Neuroendocrinology, 92 (2010), pp. 1-5 View PDF This article is free to access. CrossRefView in ScopusGoogle Scholar 2 H. Falhammar, J. Calissendorff, C. Höybye Frequency of Cushing’s syndrome due to ACTH-secreting adrenal medullary lesions: a retrospective study over 10 years from a single center Endocrine, 55 (2020), pp. 296-302 Google Scholar 3 K.B. Lois, A. Santhakumar, S. Vaikkakara, S. Mathew, A. Long, S.J. Johnson, et al. Phaeochromocytoma and ACTH-dependent Cushing’s syndrome: Tumour CRF secretion can mimic pituitary Cushing’s disease Clin Endocrinol (Oxf), 84 (2016), pp. 177-184 View article CrossRefView in ScopusGoogle Scholar 4 P. Bankhead, M. Loughrey, J. Fernandez, Y. Dombrowski, D. Mcart, P. Dunne, et al. QuPath: Open source software for digital pathology image analysis Sci. Rep, 7 (2017), pp. 1-7 Google Scholar 5 M. Savas, S. Mehta, N. Agrawal, E.F.C. van Rossum, R.A. Feelders Approach to the Patient: Diagnosis of Cushing Syndrome J Clin Endocrinol Metab, 107 (2022), pp. 3162-3174 View article CrossRefView in ScopusGoogle Scholar 6 A.M. Isidori, G.A. Kaltsas, C. Pozza, V. Frajese, J. Newell-Price, R.H. Reznek, et al. Extensive clinical experience - The ectopic adrenocorticotropin syndrome: Clinical features, diagnosis, management, and long-term follow-up J Clin Endocrinol Metab, 91 (2006), pp. 371-377 View article CrossRefView in ScopusGoogle Scholar 7 P.F. Elliott, T. Berhane, O. Ragnarsson, H. Falhammar Ectopic ACTH- and/or CRH-Producing Pheochromocytomas J. Clin. Endocr, 106 (2021), pp. 598-608 View article CrossRefView in ScopusGoogle Scholar 8 D.S. Jessop, D. Cunnah, J.G.B. Millar, E. Neville, P. Coates, I. Doniach, et al. A phaeochromocytoma presenting with Cushing’s syndrome associated with increased concentrations of circulating corticotrophin-releasing factor J. Endocrinol, 113 (1987), p. 133 View article CrossRefView in ScopusGoogle Scholar 9 T. O’Brien, W.F. Young, D.G. Davilla, B.W. Scheithauer, K. Kovacs, E. Horvath, et al. Cushing’s syndrome associated with ectopic production of corticotrophin-releasing hormone, corticotrophin and vasopressin by a phaeochromocytoma Clin Endocrinol (Oxf), 37 (1992), pp. 460-467 View article CrossRefView in ScopusGoogle Scholar 10 J. Young, M. Haissaguerre, O. Viera-Pinto, O. Chabre, E. Baudin, A. Tabarin Management of endocrine disease: Cushing’s syndrome due to ectopic ACTH secretion: an expert operational opinion Eur. J. Endocrinol, 182 (2020), pp. 29-58 View article CrossRefGoogle Scholar 11 A.M. Isidori, E. Sbardella, M.C. Zatelli, M. Boschetti, G. Vitale, A. Colao, et al. Conventional and Nuclear Medicine Imaging in Ectopic Cushing’s Syndrome: A Systematic Review J Clin Endocrinol Metab, 100 (2015), pp. 3231-3244 View article CrossRefView in ScopusGoogle Scholar 12 R. Walia, R. Gupta, A. Bhansali, R. Pivonello, R. Kumar, H. Singh, et al. Molecular Imaging Targeting Corticotropin-releasing Hormone Receptor for Corticotropinoma: A Changing Paradigm J. Clin. Endocr, 106 (2021), pp. 1816-1826 View article CrossRefGoogle Scholar 13 J.W.M. Lenders, M.N. Kerstens, L. Amar, et al. Genetics, diagnosis, management and future directions of research of phaeochromocytoma and paraganglioma: a position statement and consensus of the Working Group on Endocrine Hypertension of the European Society of Hypertension J Hypertens, 38 (2020), pp. 1443-1456 View article CrossRefView in ScopusGoogle Scholar 14 D. Taïeb, G.B. Wanna, M. Ahmad, C. Lussey-Lepoutre, N.D. Perrier, S. Nölting, et al. Clinical consensus guideline on the management of phaeochromocytoma and paraganglioma in patients harbouring germline SDHD pathogenic variants Lancet Diabetes Endocrinol, 11 (2023), pp. 345-361 View PDFView articleView in ScopusGoogle Scholar 15 K. Pacak Preoperative management of the pheochromocytoma patient J Clin Endocrinol Metab, 92 (2007), pp. 4069-4079 View article CrossRefView in ScopusGoogle Scholar Cited by (0) Sources of support: None Permission in the form of written consent from patient for use of actual test results was obtained. Cushing in silent pheochromocytoma Clinical Relevance This case highlights the importance of considering ectopic ACTH secretion by a pheochromocytoma in patients presenting with rapid progression and considerable clinical hypercortisolism concomitant with an adrenal mass and elevated plasma ACTH. This represents an unusual manifestation of a specific subtype of ACTH/CRH-secreting pheochromocytoma that did not exhibit catecholamine secretion 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 ∗ These 2 authors contributed equally to this work From https://www.sciencedirect.com/science/article/pii/S2376060524000075 1 Quote Link to comment Share on other sites More sharing options...
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