The incidence of bronchogenic carcinoma is increasing more rapidly than that of any other cancer. In 1912 Adler,1who was able to collect only 374 cases of cancer of the lung, stated, "On one point, however, there is complete consensus of opinion and that is that primary malignant neoplasms of the lung are among the rarest form of disease." Whereas it was an infrequent lesion 40 years ago, it has become one of the most frequent malignant lesions encountered in men. In the 10 years from 1938 to 1948 the number of fatalities from bronchogenic carcinoma in the United States increased 144%, from 6,732 in 1938 to 16,450 in 1948. In this same period of time the total cancer deaths from all types of cancer, increased 31%, from 149, 214in 1938 to 195,594 in 1948. From 1920 to 1948 the death rate from bronchogenic carcinoma per 100,000 population in the