Ectopic ACTH Secretion (EAS) Associated to a Well-Differentiated Peritoneal Mesothelioma

Case Report

Carmen F. Mendoza; Patricia Ontiveros; Daniel X. Xibillé; Manuel H. Rivera


BMC Endocr Disord. 2015;15(40) 

In This Article


Cushing's syndrome is caused mainly by the use of glucocorticoids in supra-physiological doses. Endogenous Cushing's syndrome is caused by an overproduction of cortisol by the adrenal glands, being of two types, ACTH dependent or independent; endogenous ACTH-dependent hypercortisolism is the most common (80–90 %) and it is caused, in about 90 % of cases, by a ACTH-producing pituitary adenoma.[1,2] ACTH production by non-pituitary tumors represents approximately 10–15 % of ACTH-dependent Cushing's syndrome. Reports concur that the tumors most commonly associated to ectopic ACTH secretion are bronchial carcinoid tumors, small-cell lung carcinoma, pulmonary adenocarcinoma, thymic carcinoid, medullary thyroid carcinoma and gastroenteropancreatic neuroendocrine tumors. Genitourinary tumors (prostate, bladder and ovarian endometrioid carcinoma) or metastatic neuroendocrine tumors of unidentified primary sites have been reported less frequently. In the St. Bartholomew series a mesothelioma was reported, diagnosed post-mortem, although histological confirmation was not obtained, and total hypophysectomy in this patient did not resolve the hypercortisolism.[3–5] There is an additional case reported in the literature, although it is a malignant pleural mesothelioma that clinically presented as coughing and pleuritic pain and was evidenced on thoracic x-rays.[6] Up to 20 % of cases with ectopic ACTH secretion derive from unidentified primary tumors.[4,7]

Peritoneal mesothelioma is a rare disease with a lineage derived from mesothelial cells. Its incidence is approximately one case per 1,000,000 persons and represents 20 to 30 % of all mesotheliomas. In general, the symptoms are not very specific and can be of two types, those related to the tumor mass, such as abdominal pain, constipation, nausea, vomiting, and ascites, or those that only present as ascites and abdominal distention. There have been reports of umbilical or inguinal hernias in some patients. There are two histopathological subtypes of peritoneal mesothelioma, the well-differentiated papillary mesothelioma (WDPM) and the benign multicystic mesothelioma. Both have a relatively indolent component, occurring mainly in women, are not related to asbestos and are treated by surgical resection. WDPM rarely suffers malignant transformation.[8,9] We present the case of a patient with a 20-year history of Cushing's syndrome, with a biochemical behavior similar to that of Cushing's disease and whose histopathological diagnosis was a well-differentiated papillary mesothelioma.