A long-term experience with oncopulmonary examinations points to their efficacy in detecting lung cancer, early forms included. As a result, the number of primary patients operated on for lung cancer or undergoing lung resection has grown in Leningrad for the past 17 years from 15.6 to 22% and from 13.2 to 19%, respectively. The best diagnostic results for central cancer have been obtained in application of bronchoscopy and with transcutaneous needle biopsy--for peripheral cancer. (The rate of morphological verification of cancer was over 96% for either procedure). The following patterns of early forms of central cancer of the lung have been identified: Ca in situ, microinvasive cancer, incipient invasive cancer and advanced invasive cancer.