Tyler Mane  -- famous for playing Michael Myers in the "Halloween" films and Sabretooth in the "X-Men" franchise -- is gearing up for the fight of his life ... revealing he's been diagnosed with an extremely rare form of breast cancer. The actor shared the shocking diagnosis over social media, telling fans he was starting chemotherapy. Tyler says on 1% of breast cancers are found in men ... and it's often not caught until the later stages. That's exactly why Tyler says he's going public with