Small-cell lung carcinoma. Cytological diagnosis

The purpose of this article is to evaluate the possibilities of cytology for lung neuroendocrine tumors (small-cell lung carcinoma and carcinoids) diagnostics. Cytology specimens obtained by bronchoscopy (n=112), biopsy of metastatic lymph nodes (n=27) or from pleural effusion (n=8) were collected within over 1 year from 147 patients and studied. Smallcell lung carcinoma was diagnosed in 143 patients, representing 23,9% of all lung carcinomas. The proportion of carcinoid tumors was 2,7% of all neuroendocrine tumors. Typical carcinoid was observed in three cases, and atypical carcinoid - in one case. Cytologic features most significant for cytological diagnosis of small-cell lung carcinoma and carcinoids were identified (n=11). Discriminant analysis demonstrated that the proportion of accurate cytological diagnosis of small-cell lung carcinoma and carcinoids was 96,69%. Cytology is a reliable method for neuroendocrine tumor diagnosis. Immunocytochemistry with neuroendocrine markers along with light microscopy should be used to differentiate small-cell lung carcinoma metastases from other tumors and non-malignant pathology in pleural effusion specimens.