A very detailed and rather complex paper describing the association between alcohol consumption and cancer has been published in the BMJ by a large group of distinguished scientists.

Members of the Forum were concerned that the authors did not separate moderate consumption from heavy consumption for their main analyses, ignored the demonstrated benefits of moderate drinking on total mortality, and did not point out other environmental influences (such as smoking, diet, obesity, etc.) that often have much larger effects on the risk of many cancers than does alcohol consumption. The authors make broad statements such as 'alcohol has negative effects on total mortality', which is not supported by the data presented in their paper, and is contradicted by most large-scale population-based studies. Overall, while this paper supports the well-known association between heavy drinking and an increased risk of upper aero-digestive and certain other cancers, it adds little information useful for the prevention of most types of cancer.
Source-Eurekalert