I think it would depend on how much I loved doing the thing and also how likely it would be to give me cancer.
For example, drinking alcohol can increase your risk of cancer, but I haven’t given that up completely because the risks are quite small and I like to have an occasional drink. The risks are higher if you drink a lot though, so I don’t do that.
That’s not an easy question to answer. It would all depend on the risks involved. If something was certain to give me cancer, then I would definitely be willing to give it up. But if something increased my risk of getting cancer by a teeny weeny amount, then I probably wouldn’t.
Short answer: yes.
Slightly longer answer: It would depend on how likely it was to cause cancer, and how much I loved it. For example, there is some evidence that partial starvation can reduce the risk of cancer. However, it could also cause other illnesses, as well as make me grumpy all the time. I’m not going to stop eating anytime soon.
I don’t smoke, I don’t drink and I’m not overweight, but my main vice is sweet things and especially chocolate. I would find really hard to give up these things, so there would have to be lots of evidences that they are cancerogenic! Most likely, I would start reducing the frequence with which I ate them.