I think the genetic component of cancer depends very much on the kind of cancer one has. Lots of other conditions have a strong genetic component - poor cardiovascular health, depression, schizophrenia, alzheimer's, strong disposition towards substance abuse, etc. I would not call it "worse" than for example the genetic likelihood of 80% of developing alzheimers at an early age (which luckily I don't personally have).

Perhaps this is a very personal view - but as I've lost relatives to all sorts of maladies including cancer I find it really hard to see cancer as the absolutely worst bogeyman in the room. That's not to say it's not bad.