Small‑cell lung carcinoma. Cytological diagnosis

Abstract

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. Small-cell 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.