Ectopic Cushing Syndrome Secondary to Diffuse Idiopathic Neuroendocrine Cell Hyperplasia-A Report of 2 Cases.

Ectopic ACTH secretion (EAS) accounts for 10% to 20% of all Cushing syndrome cases. Diffuse intrapulmonary neuroendocrine cell hyperplasia (DIPNECH), a poorly understood lung disease, is characterized by abnormal proliferation of neuroendocrine cells in the bronchial mucosa. It is thought to be a precursor of pulmonary carcinoid and has been associated with EAS in a handful of cases.