The most important two problems of cancer of the Lung complicated with pulmonary tuberculosis are as follows:
1) How many cases in which cancer and tuberculosis are found in the same pulmonary region?
2) Does actually the tuberculous focus in the lung become the original focus of cancer ?
The author described about one case in which cancer and tuberculosis had been found in the same pulmonary lobe by pathohistological tests. The result of tests pointed out the cancer formation from either tuberculous scar or cavity of the lung. But speaking from the general observation of many reported cases of pulmonary cancer with tuberculosis, although pulmonary cancer cases are far rarer than pulmonary tuberculosis in Japan, and the most of pulmonary cancer cases have their own original foci in the lung, the remarkable pathogenetical relations between cancer and tuberculosis are not recognized.
To clear up the problems above mentioned, the authors insist on the necessity to follow up the tuberculous patients of so-called cancer age.
