The Japan Cancer Society (JCS) is a nationwide civic organization that has spearheaded the private-sector fight against cancer in Japan for the past half century.

Its primary mission is to conduct a nationwide cancer-prevention campaign that raises public awareness of cancer and urges the public to undergo cancer screenings. Its regional branches across the nation annually invite about 11 million people to be screened for cancer.

JCS provides cancer information to patients, their families and the general public, through such means as telephone consultations and meetings with specialists. JCS also publishes pamphlets, gives lectures, trains specialists on cancer screening, and funds research on cancer prevention.