Yamagiwa Katsusaburō (山極 勝三郎; 23 February 1863 – 2 March 1930) was a Japanese pathologist who carried out pioneering work into the causes of cancer, and was the first to demonstrate chemical carcinogenesis. He was a 7-time Nobel Prize nominee.
Source: “Yamagiwa Katsusaburō”, English Wikipedia (CC BY-SA 4.0), excerpt