Cytology and immunocytochemistry of bronchioloalveolar carcinoma.

A study of the value of cytologic examination in the diagnosis of bronchioloalveolar carcinoma showed that fine needle aspiration (FNA) cytology is a definitive means of making the diagnosis of bronchioloalveolar carcinoma. In experienced hands, FNA cytology approached a diagnostic accuracy of 100%. With exfoliative cytology, technically adequate sputum samples offered an 82% diagnostic yield; sputum cytology should thus be considered as an adjunct method in establishing the diagnosis. Several cytologic features that strongly suggest the diagnosis of bronchioloalveolar carcinoma and help to differentiate it from adenocarcinomas of other body sites are outlined. It is also concluded that immunocytochemical stains have limited value in differentiating bronchioloalveolar carcinoma and other types of clear cell malignant neoplasms, including mesothelioma, unless a panel of antibodies is used, and are of no value in ascertaining whether the cells are benign or malignant.