Abstract

Available conventional pathologic diagnostic tools for lung cancer include sputum cytology, lung biopsy using bronchoscopy, and washing and brushing cytology. In addition, fine needle aspiration (FNA) cytology is now available and has become popular. In this study, an attempt was made to compare the relative sensitivity between conventional cytopathologic methods and FNA cytology, to study the clinical characteristics of lung cancer in which the diagnosis was established by FNA cytology, and to study the cellular findings and diagnostic criteria of lung cencers. Cases included in this study were selected from 105 patients who had been diagnosed an lung cancer at Yonsei University Medical Center during the 5-year period from January 1984 to December 1988. These 105 cases were reviewed with respect to medical records and pathologic slides and then the following conclusions were made. The mean age of cases was 58.5 years, and the sex ratio of males to females was 3.5:1. Tumors were mostly solitary in number and were mainly located at the periphery of the lung. The sensitivity of FNA cytology, sputum, and bronchial washing was as follows: FNA cytology was 0.93, sputum, 0.2, and bronchial washing, 0.14. The coincidence rate of cytopathologic diagnosis with histologic diagnosis was as follows: epidermoid carcinoma was 92%, adenocarcinoma 83%, undifferentiated large cell carcinoma 66%, and undifferentiated small cell carcinoma 100%. The false negativity of FNA cytology was 7%, which was mainly due to material insufficiency. For the differential diagnosis of histologic type, some brief criteria could be summarized. Differential diagnostic points of each histologic type were as follows: epidermoid carcinoma showed a large cellular group with keratinized cytoplasms and hyperchromatic and pyknotic nuclei, adenocarcinoma showed a glandular or ball-like arrangement by monotonous round cells, undifferentiated large cell carcinoma was mainly composed of irregular large cells and showed emperipolesis, and undifferentiated small cell carcinoma showed an Indian file appearance with molding by small, round hyperchromatic cells. In conclusion, FNA cytology is a more efficient, definite, and sensitive method for diagnosing lung cancer than other cytopathologic studies, so that careful selection of patients and experienced technique will improve the diagnostic accuracy of FNA cytology in diagnosing lung cancer.

• Keywords: Lung;Lung cancer;Fine needls aspiration;Aspiration cytology;