Studies have found a link between alcohol intake and the risk of Mouth, Throat, Larynx. Esophagus (swallowing tube from mouth to stomach), Liver and Breast cancers.
Alcohol use may be linked to colon cancer, too. In people who have already been diagnosed with cancer, alcohol intake could affect the risk for new cancers in these sites. Alcohol intake can also increase levels of estrogens in the blood. In theory this could increase the risk of estrogen receptor-positive breast cancer coming back after treatment, but studies so far have not addressed questions like this.
Should I avoid alcohol during cancer treatment?
The cancer type and stage (extent), as well as the type of treatment should be taken into account when deciding whether to drink alcohol during treatment. Alcohol, even in the small amounts used in mouthwashes, can irritate mouth sores and can even make them worse. It’s reasonable to avoid or limit alcohol for people with mouth sores. It may also be best to avoid or limit alcohol if you are starting treatment that will put you at risk for mouth sores, such as head and neck radiation or many types of chemotherapy.