Phaeochromocytoma and ACTH-dependent cushing's syndrome: tumour crf secretion can mimic pituitary cushing's disease

Cushing Syndrome Due to a Corticotropin-Releasing Hormone- and Adrenocorticotropic Hormone-Secreting Silent Pheochromocytoma

Background/Objective

Ectopic cosecretion of corticotropin-releasing hormone (CRH) and adrenocorticotropic hormone (ACTH) in silent (ie, non-catecholamine-secreting) pheochromocytoma is a rare cause of Cushing syndrome.

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 increases in the serum cortisol and plasma ACTH levels. 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 gallium-68-DOTATATE. Plasma metanephrines were normal in 2 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, the cortisol levels normalized, the hypothalamic-pituitary-adrenal 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 EAS. The use of functional imaging radioisotopes (eg, 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, whereas alpha blockade prevents the onset of an adrenergic crisis.

Conclusion

We present a rare case of EAS due to a silent pheochromocytoma that cosecreted ACTH and CRH. Pheochromocytoma should be considered in patients with EAS who have an adrenal mass even in the absence of excessive catecholamine secretion.

[A rare cause of hypercorticism: ACTH-secreting pheochromocytoma (a case report)]

Ectopic ACTH-secreting pheochromocytoma is a very rare cause of Cushing´s syndrome, posing diagnostic and therapeutic challenges. We here report the case of a female patient with suspected severe Cushing´s syndrome associated with melanoderma, arterial hypertension resistant to triple therapy and unbalanced diabetes treated with insulin therapy. Biologically, urinary ethoxylated, 24-hour urinary free cortisol and ACTH were very high. Imaging showed a 3.5 cm left adrenal mass. The patient underwent left adrenalectomy after medical preparation, with good clinico-biological outcome. Anatomopathological examination confirmed the diagnosis of pheochromocytoma. This case study highlights the importance of measuring methoxylated derivatives in any patient with ACTH-dependent Cushing´s syndrome associated with an adrenal mass. The aim is to ensure early treatment and avoid life-threatening complications.

Ectopic ACTH- and/or CRH-Producing Pheochromocytomas

CONTEXT

The characteristics of catecholamine-secreting pheochromocytomas have been well studied. However, less is known about the characteristics, management and outcome in patients with ectopic adrenocorticotropic hormone (ACTH) and/or corticotrophin-releasing hormone (CRH)-secreting pheochromocytomas.

OBJECTIVE

To review the characteristics and outcomes of ACTH- and/or CRH-secreting pheochromocytomas.

DATA SOURCE

A systematic search of PubMed/MEDLINE and Web of Science, identifying relevant reports published up to 10 February 2020.

STUDY SELECTION

Original articles, including case reports and case series, reporting individual patient data from patients with ACTH- and/or CRH-secreting pheochromocytomas.

DATA EXTRACTION

Information on sex, age, symptoms at presentation, comorbidities, biochemistry, imaging, histopathology, and outcomes was extracted.

DATA SYNTHESIS

We identified 91 articles reporting on 99 cases of ACTH- and/or CRH-secreting pheochromocytomas (CRH-secreting n = 4). Median age at diagnosis was 49 years (interquartile range 38-59.5) with a 2:1 female to male ratio. Most patients presented with clinical Cushing syndrome (n = 79; 81%), hypertension (n = 87; 93%), and/or diabetes (n = 50; 54%). Blood pressure, glucose control, and biochemical parameters improved in the vast majority of patients postoperatively. Infections were the most common complication. Most cases (n = 70, 88%) with reported long-term outcome survived to publication (median follow-up 6 months).

CONCLUSION

Ectopic ACTH- and/or CRH-secreting pheochromocytoma should be considered in patients presenting with ACTH-dependent Cushing syndrome and adrenal mass. Despite the challenge in diagnosis, patient outcomes appear favorable.

A rare cause of severe Cushing's syndrome

SUMMARY

Ectopic adrenocorticotropic hormone (ACTH) production is an uncommon cause of Cushing's syndrome and, rarely, the source can be a phaeochromocytoma. A 55-year-old man presented following an episode of presumed gastroenteritis with vomiting and general malaise. Further episodes of diarrhoea, joint pains and palpitations followed. On examination, he was hypertensive with no clinical features to suggest hypercortisolaemia. He was subsequently found to have raised plasma normetanephrines of 3.98 nmol/L (NR <0.71) and metanephrines of 0.69 nmol/L (NR <0.36). An adrenal CT showed a 3.8 cm right adrenal nodule, which was not MIBG-avid but was clinically and biochemically consistent with a phaeochromocytoma. He was started on alpha blockade and referred for right adrenalectomy. Four weeks later, on the day of admission for adrenalectomy, profound hypokalaemia was noted (serum potassium 2.0 mmol/L) with non-specific ST-segment ECG changes. He was also diagnosed with new-onset diabetes mellitus (capillary blood glucose of 28 mmol/L). He reported to have gained weight and his skin had become darker over the course of the last 4 weeks. Given these findings, he underwent overnight dexamethasone suppression testing, which showed a non-suppressed serum cortisol of 1099 nmol/L. Baseline serum ACTH was 273 ng/L. A preliminary diagnosis of ectopic ACTH secretion from the known right-sided phaeochromocytoma was made and he was started on metyrapone and insulin. Surgery was postponed for 4 weeks. Following uncomplicated laparoscopic adrenalectomy, the patient recovered with full resolution of symptoms.

LEARNING POINTS

Phaeochromocytomas are a rare source of ectopic ACTH secretion. A high clinical index of suspicion is therefore required to make the diagnosis. Ectopic ACTH secretion from a phaeochromocytoma can rapidly progress to severe Cushing's syndrome, thus complicating tumour removal. Removal of the primary tumour often leads to full recovery. The limited literature suggests that the presence of ectopic Cushing's syndrome does not appear to have any long-term prognostic implications.

Possible pitfalls in the workup of ectopic ACTH secretion illustrated by four rare cases

In this case report, we highlight four different cases of ectopic adrenocorticotropic hormone (ACTH) secretion with different pitfalls in the diagnostic workup. Ectopic ACTH secretion (EAS) is an uncommon cause of Cushing’s syndrome that accompanies a variety of tumours. It is associated with significant morbidity and mortality. This underlines the importance of early and adequate diagnosis. We will review the causes of EAS and their presentation to increase awareness of this rare and progressive disease.

Ectopic cushing's syndrome due to corticotropin releasing hormone

Cushing's syndrome (CS) secondary to corticotropin releasing hormone (CRH) producing tumors is rare. In this paper we present an Iranian patient who was admitted to our hospital with classic signs and symptoms of CS. Laboratory evaluation revealed high serum and urine cortisol which could not be suppressed with dexamethasone. Abdominal CT scan revealed a mass in abdominal cavity. A percutaneous needle biopsy was performed and histopathologic evaluation revealed that the mass was a neuroendocrine tumor. A multi-disciplinary approach including resection of the mass, bilateral adrenalectomy somatostatin analogue and chemotherapy was applied for management of the disease. Extensive review of English literature focusing on the topic from 1971 to 2018 revealed that there have been only 75 similar cases. Clinical, laboratory, imaging, histopathologic characteristics and managements of these patients will also be discussed in this paper.

[Ectopia of the adrenal]

Ectopia of nodular adrenocortical tissue is very frequently found in the periadrenal region. It corresponds to accessory adrenal tissue and is a normal variant. Ectopia in more distant regions are found in inner male or female genitalia. Strong long-lasting hyperstimultions induce hyperplasia and simulate true tumors ("adrenal rest tumors"). Real autonomic tumors from ectopic adrenal tissue with or without hyperfunction are rare. Ectopia of adrenomedullary tissue are nearly exclusively found in the surroundings of normal medulla. Ectopia in the adrenals corresponds almost exclusively with thyroid tissue. Ectopic secretion of hormones, mostly ACTH, can be found in pheochromocytomas and induces hyperfunction (Cushing's syndrome).

Malignant Pheochromocytomas/Paragangliomas and Ectopic Hormonal Secretion: A Case Series and Review of the Literature

Malignant pheochromocytomas (PCs) and paragangliomas (PGLs) are rare neuroendocrine neoplasms defined by the presence of distant metastases. There is currently a relatively paucity of data regarding the natural history of PCs/PGLs and the optimal approach to their treatment. We retrospectively analyzed the clinical, biochemical, imaging, genetic and histopathological characteristics of fourteen patients with metastatic PCs/PGLs diagnosed over 15 years, along with their response to treatment. Patients were followed-up for a median of six years (range: 1-14 years). Six patients had synchronous metastases and the remaining developed metastases after a median of four years (range 2-10 years). Genetic analysis of seven patients revealed that three harbored succinate dehydrogenase subunit B/D gene (SDHB/D) mutations. Hormonal hypersecretion occurred in 70% of patients; normetanephrine, either alone or with other concomitant hormones, was the most frequent secretory component. Patients were administered multiple first and subsequent treatments including surgery (n = 12), chemotherapy (n = 7), radionuclide therapy (n = 2) and radiopeptides (n = 5). Seven patients had stable disease, four had progressive disease and three died. Ectopic hormonal secretion is rare and commonly encountered in benign PCs. Ectopic secretion of interleukin-6 in one of our patients, prompted a literature review of ectopic hormonal secretion, particularly from metastatic PCs/PGLs. Only four cases of metastatic PC/PGLs with confirmed ectopic secretion of hormones or peptides have been described so far.

Metyrapone-responsive ectopic ACTH-secreting pheochromocytoma with a vicious cycle via a glucocorticoid-driven positive-feedback mechanism

In ectopic ACTH-secreting pheochromocytoma, combined ACTH-driven hypercortisolemia and hypercatecholaminemia are serious conditions, which can be fatal if not diagnosed and managed appropriately, especially when glucocorticoid-driven positive feedback is suggested with a high ACTH/cortisol ratio. A 46-year-old man presented with headache, rapid weight loss, hyperhidrosis, severe hypertension and hyperglycemia without typical Cushingoid appearance. Endocrinological examinations demonstrated elevated plasma and urine catecholamines, serum cortisol and plasma ACTH. Moreover, his ACTH/cortisol ratio and catecholamine levels were extremely high, suggesting catecholamine-dominant ACTH-secreting pheochromocytoma. Computed tomography revealed a large right adrenal tumor. ¹⁸F-FDG positron emission tomography showed uptake in the area of the adrenal tumor, while ¹²³I-metaiodobenzylguanidine scintigraphy showed no accumulation. His plasma ACTH level paradoxically became elevated after a dexamethasone suppression test. After metyrapone administration, not only serum cortisol but also plasma ACTH levels were exponentially decreased almost in parallel, suggesting a glucocorticoid-driven positive-feedback regulation in this rapidly exacerbated ectopic ACTH-producing pheochromocytoma. Interestingly enough, plasma catecholamine levels were also decreased by metyrapone, although they remained extremely high. He became severely dehydrated due to hypoadrenalism requiring hydrocortisone supplementation. His clinical signs and symptoms were improved, and right adrenalectomy was performed uneventfully, resulting in complete remission of pheochromocytoma and Cushing's syndrome. A glucocorticoid-driven positive-feedback regulation in this ectopic ACTH-secreting pheochromocytoma created a vicious cycle with rapid exacerbation of both hypercortisolemia and hypercatecholaminemia with extremely elevated plasma ACTH level. Metyrapone was clinically effective to stop this vicious cycle; nonetheless, great care must be taken to avoid hypoadrenalism especially when hypercatecholaminemia remained.

An unusual case of ectopic corticotrophin-releasing hormone syndrome caused by an adrenal noncatecholamine-secreting pheochromocytoma: a case report

BACKGROUND

Pheochromocytoma, especially for noncatecholamine-secreting pheochromocytoma, is an extremely rare cause of ectopic corticotrophin-releasing hormone (CRH) syndrome.

CASE PRESENTATION

A 27-year-old Chinese woman was administered dexamethasone for a skin allergy, but her general condition rapidly deteriorated over a month. She was subsequently hospitalized for typical clinical features of Cushing's syndrome. Endocrinological investigation confirmed severe hypercortisolism along with elevated plasma adrenocorticotropin hormone (ACTH). However, magnetic resonance imaging (MRI) revealed no pituitary adenoma. Abdominal contrast-enhanced computed tomography (CT) revealed a 6.5 cm heterogeneous right adrenal mass with mildly contrast enhancement. The tumor was found during a routine physical check-up at a local hospital 16 months ago; however, the patient did not have any symptoms and did not seek further medical attention at that time. Laparoscopic resection of the right adrenal tumor led to a rapid remission of Cushing's syndrome. Based on pathological findings and the presence of normal catecholamine metabolites in her serum and urine, the patient was diagnosed with noncatecholamine-secreting pheochromocytoma. Immunohistochemical staining of the adrenal tumor revealed positive staining for CRH and negative staining for ACTH.

CONCLUSIONS

This is an extremely rare case of ectopic CRH syndrome caused by an adrenal noncatecholamine-secreting pheochromocytoma. Both ectopic ACTH syndrome and ectopic CRH syndrome should be considered in patients presenting with ACTH-dependent Cushing's syndrome caused by extrapituitary diseases.

A rare case of an ACTH/CRH co-secreting midgut neuroendocrine tumor mimicking Cushing's disease

Ectopic ACTH/CRH co-secreting tumors are a very rare cause of Cushing’s syndrome and only a few cases have been reported in the literature. Differentiating between Cushing’s disease and ectopic Cushing’s syndrome may be particularly difficult if predominant ectopic CRH secretion leads to pituitary corticotroph hyperplasia that may mimic Cushing’s disease during dynamic testing with both dexamethasone and CRH as well as bilateral inferior petrosal sinus sampling (BIPSS). We present the case of a 24-year-old man diagnosed with ACTH-dependent Cushing’s syndrome caused by an ACTH/CRH co-secreting midgut NET. Both high-dose dexamethasone testing and BIPSS suggested Cushing’s disease. However, the clinical presentation with a rather rapid onset of cushingoid features, hyperpigmentation and hypokalemia led to the consideration of ectopic ACTH/CRH-secretion and prompted a further workup. Computed tomography (CT) of the abdomen revealed a cecal mass which was identified as a predominantly CRH-secreting neuroendocrine tumor. To the best of our knowledge, this is the first reported case of an ACTH/CRH co-secreting tumor of the cecum presenting with biochemical features suggestive of Cushing’s disease.

Genetic Aspects of Pituitary Adenomas

Although most of pituitary adenomas are benign, they may cause significant burden to patients. Sporadic adenomas represent the vast majority of the cases, where recognized somatic mutations (eg, GNAS or USP8), as well as altered gene-expression profile often affecting cell cycle proteins have been identified. More rarely, germline mutations predisposing to pituitary adenomas -as part of a syndrome (eg, MEN1 or Carney complex), or isolated to the pituitary (AIP or GPR101) can be identified. These alterations influence the biological behavior, clinical presentations and therapeutic responses, and their full understanding helps to provide appropriate care for these patients.

Frequency of Cushing's syndrome due to ACTH-secreting adrenal medullary lesions: a retrospective study over 10 years from a single center

Cushing's syndrome due to ectopic adrenocorticotropic hormone production from adrenal medullary lesions has occasionally been described. We retrospectively reviewed all 164 cases of Cushing's syndrome and 77 cases of pheochromocytomas during 10 years. Of all cases with Cushing's syndrome, only two cases (1.2 %) were due to ectopic adrenocorticotropic hormone production from adrenal medullary lesions (one case of pheochromocytoma and one case of adrenal medullary hyperplasia). Of all pheochromocytomas only the above-mentioned case (1.3 %) also gave rise to an ectopic adrenocorticotropic hormone syndrome. The clinical presentation of adrenocorticotropic hormone-secreting pheochromocytoma and adrenal medullary hyperplasia can be anything from mild to dramatic. These are rare conditions important to bear in mind in the workup of a patient with Cushing's syndrome or with pheochromocytoma. The identification of ectopic adrenocorticotropic hormone secretion from adrenal medullary lesions can be life-saving.