Randy Moss just revealed he’s battling cancer.

The Minnesota Vikings legend announced the sad news on his Instagram page Friday afternoon … telling his 640,000-plus followers that he’s been in the hospital for the last six days dealing with surgery related to the disease.

Moss appeared on camera to give his fans the update — and he needed a cane to move around. The 47-year-old was in great spirits, though — as he wore a lavender and black “Team Moss” shirt that read “Let’s Moss Cancer.”