On September 6, 2001, Koivu was diagnosed with Burkitt's lymphoma, a non-Hodgkin's lymphoma and he nearly all of the 2001–02 season. After he had been suffering serious pains in his stomach and was vomiting went to see the Canadiens' physician David Mulder, who, after many tests discovered the cancer. He was expected to miss the season but he made a comeback in time for the last few games. The fans gave Koivu an eight-minute standing ovation when he skated onto the Molson Centre ice for the first time on April 9, 2002. For both his courage and his off-ice team leadership while he was undergoing cancer treatment, Koivu was awarded the Bill Masterton Memorial Trophy following the 2002 playoffs.