A note from history: landmarks in history of cancer, part 5.

In the 3 decades from 1910 to 1940, more progress took place in cancer research and the diagnosis and treatment of cancers than during the prior centuries combined. The discovery of several carcinogens, precancerous conditions, and hereditary cancers adduced new thoughts about the genesis of cancers. Even though diagnostic radiology and radiation therapy became apposite specialties, surgery retained its primacy in the treatment of cancer patients. The delineation of new and distinct neoplastic entities, several precancerous lesions, and noninvasive carcinomas as well as the introduction of histopathologic grading of cancers promulgated cogent changes in therapy. Yet, with all the advances in the diagnosis and treatment of cancers, very little betterment could be demonstrated in the overall survival of patients, and by the end of the 1930s, cancer became the second most common cause of death in the United States.