Intake of coffee, caffeine and other methylxanthines and risk of Type I vs Type II endometrial cancer

Background: Coffee and other sources of methylxanthines and risk of Type I vs Type II endometrial cancer (EC) have not been evaluated previously. Methods: Prospective cohort of 23 356 postmenopausal women with 471 Type I and 71 Type II EC cases. Results: Type I EC was statistically significantly associated with caffeinated (relative risk (RR) 0.65 for 4þ cups per day vsp1 cup per month: 95 % confidence interval (CI): 0.47–0.89) but not decaffeinated (RR 0.76; 95 % CI: 0.50–1.15) coffee intake; there were no associations with tea, cola or chocolate, or for Type II EC. The inverse association with caffeinated coffee intake was specific to women with a body mass index 30þ kgm 2 (RR 0.56; 95 % CI: 0.36–0.89). Conclusion: Coffee may protect against Type I EC in obese postmenopausal women. Following water and tea, coffee is the third most consumed beverage in the world (Bushman, 1998; La Vecchia and Tavani, 2007). A recent meta-analysis reported an inverse association of coffee intake with endometrial cancer (EC) risk (Je and Giovannucci, 2011). The presence of antioxidants and other chemopreventive compounds in coffee may explain its antic-arcinogenic effect (Vivani, 1993; Cavin et al, 2002). However, i