Fine needle aspiration cytopathology of bronchial carcinoid tumors: an analytical study of the cells.

While frequently considered to originate in a common stem-cell of neuroendocrine origin, bronchial carcinoid tumors and small-cell anaplastic carcinomas differ significantly in their biologic potential and treatment. Patient management is often dependent on the diagnostic specificity of a pulmonary fine needle aspiration specimen. This study evaluated the cellular features in fine needle aspiration samples from seven bronchial carcinoid tumors and four small-cell anaplastic carcinomas of the "intermediate" type. Planimetric measurements were performed on tracings of 1,100 cells. An analysis of specific cytoplasmic and nuclear features was also obtained on 2,200 cells. Significant quantitative and qualitative differences in the cytomorphology of the cells derived from bronchial carcinoid and small-cell anaplastic neoplasms were obtained, clearly demonstrating that differentiation of these neoplasms is possible on a cytopathologic basis in fine needle aspiration samples.