Lung tumors with neuroendocrine morphology. A perspective for the new millennium.

Pulmonary neuroendocrine cell proliferations represent a spectrum of lesions ranging from reactive processes to highly malignant carcinomas. The histogenesis and classification of these lesions is controversial and confusing. Radiologists are performing many diagnostic fine needle aspirations and biopsies, and must be familiar with these tumors. This article describes the various lesions and provides guidelines for their differential diagnosis.