Giants in History: Koichi Ichikawa

Nobel-worthy cancer research 

Koichi Ichikawa ( 1888 - 1948)


In 1915, Koichi Ichikawa working as research assistant with pathologist Katsusaburo Yamagiwa became the first to prove that chronic exposure to chemicals can cause cancer. At Tokyo Imperial University, they induced tumour growth by rubbing coal tar on rabbit ears. Yamagiwa was nominated for a Nobel Prize in Physiology or Medicine in 1925, 1926 and 1928, and again in 1936 with Ichikawa. They lost out to another scientist whose cancer research was soon found to be wrong, yet the prize was maintained. Today, the first samples of induced tumour are displayed in specimen rooms at the University of Tokyo and Hokkaido University, where Ichikawa worked in veterinarian medicine and comparative pathology.

University of Tokyo
Hokkaido University
Hokkaido Imperial University