Cigarette Smoking and Endometrial Cancer

A case control study of 510 cases of endometrial cancer and 727 controls with other types of cancer aged 30-69 by the Drug Epidemiology Unit is described. Epidemiologic case-control studies suggest that smoking in certain groups of women lowers the risk of endometrial cancer. Possibly this effect if real is due to the fact that smoking lowers estrogen levels. Endometrial cancer is known to be estrogen dependent. 4 studies found the risk of endometrial cancer lower in smokers but only one was statistically significant. 2 studies found the effect limited to postmenopausal women. Current smokers in the DEU study has 0.7 times the risk of endometrial cancer as never-smokers. Those smoking >25 cigarettes daily had a risk of 0.5. Taking a long list of factors into account in multiple regression analysis including body mass parity age age at menopause oral contraceptive and conjugated estrogen use among others did not alter the results.