[The coexistence of pulmonary tuberculosis and lung cancer]

To summarize the clinical features of the coexistence of lung cancer (LC) and pulmonary tuberculosis (TB) from the reports in Japan. The frequency is about 2-4% of LC and about 1-2% of TB and elderly men are frequent. Lung cancer is mainly from periphery origin and squamous cell carcinoma, histopathologically. Cavitary lesions are few of pulmonary tuberculous lesions and those are not occasionally detectable in the pictures. The lesions of LC and TB are mainly located in same lung, and sometimes in same lobe. By the interval of diagnosis of LC and TB, the patients are divided to three groups; TB proceeding type, LC proceeding type and coexistence type. Because of the very high TB infected rate of elder people in Japan, who have also high incidence rate of LC, the rate of coexistence of LC and TB is high, so the patients suffered from either disease are necessary to follow up carefully as the high-risk group of other disease.