Diffuse idiopathic pulmonary neuroendocrine cell hyperplasia: case report and review of literature.

Diffuse idiopathic pulmonary neuroendocrine cell hyperplasia is a rare condition affecting mostly women in the fifth and sixth decades of life. Here we present a case of its accidental finding in the lung parenchyma of a 56-year-old non-smoker female. In the periphery of the right middle lobe, linear and nodular proliferations were detected in the wall of the small bronchi and terminal and respiratory bronchioles. Under the pleura, several tumorlets were located. Immunohistologically, neuroendocrine cells were positive with antibodies against chromogranin A, synaptophysin, CD56, serotonin (weak positivity of some cells only), calcitonin, GRP/bombesin, cytokeratin 7 and TTF-1.