Studies on cytological diagnosis of lung cancer

The usefulness of combining aerosol induction with Saccomanno's concentration method was examined in 240 patients who were diagnosed as having lung cancer by fiberoptic bronchoscopy and /or by thoracotomy. By the combined method, satisfactory sputum was obtained from 97.1% of the patients. Sputum cytology gave a positive diagnosis in 57.5% of the patients. Positive rates were 84.8% for patients with centrally located lung cancer and 38.3% for patients with peripherally located lung cancer. With regard to histological classification, positive rates of sputum cytology were 36.9% for adenocarcinomas, 76.8% for squamous cell carcinomas and 73.3% for small cell carcinomas. This combined method resulted in a improved yield of satisfactory sputum as well as positive cytology compared with a conventional method using spontaneous sputum, which gave only 23.3% positive cytology. The combined method may be useful for the diagnosis of lung cancer in mass surveys.