Diffuse Idiopathic Neuroendocrine Cell Hyperplasia

Diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH) is a rare clinicopathologic syndrome with little known of its clinical course and treatment options. We present 4 cases of DIPNECH with 2 to 14 years follow up and a discussion of clinical presentation, pathology, and their management. A high index of suspicion is required to recognize this entity, which is characterized by an insidious onset of a mixed obstructive and/or restrictive pattern of lung disease with reticulonodular infiltrates bilaterally and a predilection for middle-aged women. Immunohistochemical studies reveal the absence of estrogen or progesterone receptors in these patients. Patients with carcinoid tumors arising within DIPNECH have an excellent long-term prognosis.