Diffuse Idiopathic Pulmonary Neuroendocrine Cell Hyperplasia With Progression to Neuroendocrine Tumor.

Diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH) is a parenchymal lung disease characterized by a proliferation of neuroendocrine cells in the bronchial wall, with possible local invasion and occasional development of tumorlets. It is considered to be a precursor lesion as it can progress to neuroendocrine tumors (NETs). At presentation, approximately one-half of patients with DIPNECH have a synchronous diagnosis of NET. Here, we present the case of a 95-year-old woman with progressive exertional dyspnea. She was found to have an obstructive airway syndrome and long-lasting progressive bilateral pulmonary nodules, with a distribution and growth pattern suggestive of DIPNECH, as well as possible progression to NET in the larger lesions. A transthoracic needle aspiration biopsy of a pulmonary nodule was performed, confirming the diagnosis of NET, evolving from DIPNECH.