The relationship between cancer and drugs, including alcohol, has several aspects. One is the question of carcinogenesis; that is, whether alcohol and other abused substances cause cancer. Another is the relationship between prescription medications and cancer. A third is the complications of cancer treatment in patients with a history of substance abuse.

Carcinogenesis

The likelihood of a substance to cause cancer is called carcinogenicity; this is determined in several ways. The first is to see if cells grown in vitro (in a test tube) with the potential carcinogen develop cell-structure abnormalities in the new-grown cells. The second is to see if the substance will result in cancers in animals. The third is to look at the clinical course of a disease in a human patient. Finally, the outcomes in a group of people exposed to the substance will be compared to outcomes...