A Case of Cushing`s Syndrome in ACTH - secreting Mediastinal Paraganglioma

Abstract

Paragangliomas are unusual neuroendocrine cell tumors arising from paraganglia, of which ACTH-secreting cases in the mediastinum are exremely rare. A 51-year-old woman was admitted for generalized edema and weakness which began 5 months ago. Chest X-ray and CT scan revealed a tumor mass in the anterior mediastinum. The plasma cortisol and ACTH levels were very high. Other sources secreting ACTH, except mediastinal mass, were not found. Surgical excision of mediastinal mass and left supraclavicular lymph node was performed. The postoperative microscopic finding and immunohistochemical staining revealed organoid tumor cell nests (zellballen) and S-100 protein positive sustentacular cells which are characteristics of paraganglioma. This was thus a case of Cushing’s syndrome resulting from ectopic ACTH production in anterior mediastinal paraganglioma.

Disseminated large cell neuroendocrine carcinoma associated with ectopic adrenocorticotropic hormone secretion

“…Again, to the best of our knowledge, there is only one reported case of a superior mediastinal paraganglioma associated with EAS, and only one reported case of primary lung LCNEC associated with EAS. 21,22 No case of superior mediastinal lymphoma associated with EAS was found in the literature. Thus, poorly differentiated NEC with large cell morphology associated with EAS arising from the superior mediastinum is rare.…”

Ectopic Cushing’s syndrome due to retroperitoneal ACTH-producing paragangliomas

“…EAS cases due to paraganglioma have been reported in only 10 patients (Table 1). [4][5][6][7][8][9][10][11][12][13] The tumour was located in the mediastinum in four of them, in paranasal sinus in three, and in the retroperitoneum in three patients. Only one patient had malignant tumours located throughout the thorax and abdomen.…”

Hypoglycemia due to Ectopic Release of Insulin from a Paraganglioma

“…In contrast, there is little evidence of such a secretion by extra-adrenal pheochromocytomas (paragangliomas) [17]. Adrenocorticotrophic hormone (ACTH), beta-endorphine, pancreatic polypeptide, interleukine-6 and androgens are among the hormones secreted by paragangliomas [18,19,20,21,22,23,24,25]. To date, insulin secretion from a paraganglioma has been reported only by Fujino et al [6].…”

“…Their small size and retroperitoneal localization and paucity of hormonal secretion render them difficult to diagnose. Besides their ability to secrete epinephrine, norepinephrine, dopamine and chromogranin, these tumors can rarely produce other hormones and neurotransmitters [18,19,20,21,22,23,24,25]. Until now, there has been a single case report describing a female patient with hypoglycemic attacks secondary to an insulin-secreting paraganglioma [6].…”