Cancer is probably selected against to a degree. At least for most normal healthy males, not dying prematurely of cancer means you've got probably 50 or so yea

Cancer is probably selected against to a degree. At least for most normal healthy males, not dying prematurely of cancer means you've got probably 50 or so years to pass on your genes. If a cancer causing mutation kills you at 30, you may still have the chance to pass on your genes, but you're still being outcompeted in the larger gene pool by those who don't die early and have more children than you. And if not you, then your children who die prematurely may not procreate. Evolution doesn't really have much noticeable effect at the scale of single generations anyways.