Alcohol consumption and risk of hematological malignancies: A meta-analysis of prospective studies

Current convincing evidence suggests that alcohol intake increases the risk of several carcinomas, which might subsequently lead to a recommendation toward limiting alcohol consumption. However, there are accumulating data worth meta-analyzing that show a different effect on the risk of hematological malignancies. Eligible cohort studies were sought in PubMed database up to August 31, 2016. Separate analyses were performed by subtype of hematological malignancy (non-Hodgkin lymphoma [NHL] and subtypes, Hodgkin lymphoma [HL], leukemia and subtypes), time status (ever, current, former), level of consumption (light, moderate, heavy), alcoholic beverage (total alcohol, beer, liquor, wine) and gender. Moderate and heavy alcohol consumption were significantly associated with reduced risk of NHL (relative risk [RR] = 0.85, 95% confidence interval [CI]: 0.80-0.90 and RR = 0.73, 95%CI: 0.60-0.89, respectively); a protective trend was also shown for light alcohol intake (RR = 0.93, 95%CI: 0.87-1.00). Specifically, beer consumption was associated with reduced NHL risk (RR = 0.88, 95%CI: 0.81-0.95). However, the association regarding other alcoholic beverages seemed null. The beneficial effects of alcohol mainly pertained to Diffuse Large B-Cell Lymphoma (DLBCL) (RR = 0.83, 95%CI: 0.77-0.89) and Follicular Lymphoma (FL) (RR = 0.85, 95%CI: 0.78-0.93). There was also no association between alcohol consumption and risk of HL or leukemias. In contrast to most solid malignancies, alcohol seems to confer a protective effect on NHL risk, especially on DLBCL and FL subtypes, with beer being notably beneficial.