"Two months ago, I was diagnosed with cancer of the digestive tract," Fignon said in an interview broadcast with Europe-1 radio on Thursday. "I started chemotherapy two weeks ago. It's going well." Fignon added that he will undergo more tests after the Tour de France.
French newspaper Le Parisien also quotes him as saying that the cancer is advanced.
Fignon said doctors told him the cancer was unlikely to have been caused by the performance enhancing products he took during his career.
Fignon has written a book, We were Young and Carefree, in which he describes his use of amphetamines and cortisone.
"I don't know whether or not that played a role," Fignon said.
"I don't know at all. It's impossible to say, yes or no. According to the doctors, apparently not."
The 48-year-old Frenchman won the Tour in 1983 and 1984 and several other prestigious cycling races during his career.
