Disseminated large cell neuroendocrine carcinoma associated with ectopic adrenocorticotropic hormone secretion

Abstract

Ectopic adrenocorticotropic hormone (ACTH) secretion is associated with a heterogeneous spectrum of neuroendocrine tumours (NETs) as well as non-NET tumours. Both ectopic ACTH secretion (EAS) and NETs are relatively uncommon. Large cell neuroendocrine carcinoma (LCNEC) is considered to be a poorly differentiated NET, and is very rarely associated with EAS. Only case reports of EAS associated with LCNEC have been documented. We present a case of disseminated LCNEC associated with EAS. The LCNEC was diagnosed on bone marrow trephine biopsy, and the likely but unproven primary was a NET arising from the superior mediastinum, which also caused superior vena cava (SVC) syndrome at presentation.