[New cancer therapies: balancing risk and benefit]

Irinotecan has been approved in Japan, France and USA, however, its clinical usefulness seems to be differently understood. There is a strong opinion, especially in Japan, that the drug is too toxic since it may harm as many patients than it helps. On the contrary, irinotecan is well accepted to the US cancer chemotherapy practices. With irinotecan as a typical example of new chemotherapeutic agents, benefit and risk of cancer chemotherapy is discussed. Differences in cancer chemotherapy practices between Japan and USA are discussed as well.