While alcohol in excess has been linked to an increased chance of cancer, several studies of resveratrol (a bioactive compound found in the skin of grapes, red wine, cranberries and blueberries) may have a preventative effect, or even a mild therapeutic effect.
Recently, research in Brazil (June 2018) observed resveratrol stopping mutated p53 proteins (these proteins suppress tumors by protecting healthy cells, and killing off cancer cells). They are continuing their research to isolate which molecules have this activity, so drugs can be created that target p53 mutations.
This doesn't mean you should consume large amounts of alcohol to try to fight cancer, but for the most part, you may not need to quit cold turkey either. A bit a red wine, along with other cancer fighting foods might be just what your body wants. And if it reduces your stress, there may be benefits there as well.
As always, talk to your doctor about what is right for your body.