Alcohol intake and endometrial cancer risk: a meta-analysis of prospective studies cancer
Previous studies on alcohol intake in relation to endometrial cancer risk have produced inconsistent results. A recent study undertook a meta-analysis of seven cohort studies, including 1 511 661 participants and 6086 endometrial cancer cases, were included in the dose-response random-effect meta-regression model. Compared with non-drinkers, women drinking less than 1 drink of alcohol (13g of ethanol) per day had a lower risk for endometrial cancer; this risk was lower by 4% (95% confidence interval (95% CI): 0.93-1.00) for consumption up to 0.5 drink per day and by 7% (95% CI: 0.85 1.02) for consumption up to 1 drink. However, the researchers found evidence of an increased risk for endometrial cancer for intakes higher than two alcoholic drinks per day: compared with non-drinkers, the risk was higher by 14% (95% CI: 0.95-1.36) for 2-2.5 drinks per day and by 25% (95% CI: 0.98-1.58) for >2.5 drinks per day.
The authors conclude that the meta-analysis indicates a possible J-shaped relationship between alcohol intake and endometrial cancer risk. 

Source: Alcohol intake and endometrial cancer risk: a meta-analysis of prospective studies. Author: Friberg E; Orsini N; Mantzoros CS; Wolk A Journal: British Journal of Cancer.  Vol 103, No 1, 2010, pp127-131