Theoretical potential for endometrial cancer prevention through primary risk factor modification: Estimates from the EPIC cohort.

Endometrial cancer (EC) incidence rates vary ~10-fold worldwide, in part due to variation in EC risk factor profiles. Using an EC risk model previously developed in the European EPIC cohort, we evaluated the prevention potential of modified EC risk factor patterns and whether differences in EC incidence between a European population and low-risk countries can be explained by differences in these patterns. Predicted EC incidence rates were estimated over 10 years of follow-up for the cohort before and after modifying risk factor profiles. Risk factors considered were: body mass index (BMI, kg/m2 ), use of postmenopausal hormone therapy (HT) and oral contraceptives (OC) (potentially modifiable); and, parity, ages at first birth, menarche and menopause (environmentally conditioned, but not readily modifiable). Modeled alterations in BMI (to all ≤23 kg/m2 ) and HT use (to all non-HT users) profiles resulted in a 30% reduction in predicted EC incidence rates; individually, longer duration of OC use (to all ≥10 years) resulted in a 42.5% reduction. Modeled changes in not readily modifiable exposures (i.e., those not contributing to prevention potential) resulted in ≤24.6% reduction in predicted EC incidence. Women in the lowest decile of a risk score based on the evaluated exposures had risk similar to a low risk countries; however, this was driven by relatively long use of OCs (median = 23 years). Our findings support avoidance of overweight BMI and of HT use as prevention strategies for EC in a European population; OC use must be considered in the context of benefits and risks.

Incidence and Trend of Type I and II Endometrial Cancer in Women from Two Population-Based European Cancer Registries (1998-2012).

Endometrial cancer (EC) is the most frequent female genital tract cancer in Europe. This cohort study aimed to determine age-standardised incidence rates and long-term trends of type I and II endometrial cancer in women from population-based cancer registries in the Region of Murcia (Spain) and the Bas-Rhin area (France). Data of new cases of endometrial cancer between 1998 and 2012 were obtained from the Murcia and Bas-Rhin cancer registries. In that period, 3756 cases of endometrial cancer were recorded, with 3270 corresponding to type I EC and 486 corresponding to type II EC. The Bas-Rhin area presented higher age-adjusted incidence rates than those in the Region of Murcia for both type I EC (24.2 and 19.3 cases/100,000 person-years (py), respectively) and type II EC (4.4 and 2.3 cases/100,000 py, respectively). Joinpoint regression showed no changes in trends. In both populations, there was an increasing trend for both EC types, but the trend was steeper in the Region of Murcia and larger overall for type II EC. Finally, a significant increase was observed in the annual trend of type II EC. Further studies are warranted to determine the potential risk factors, and continued efforts are needed to improve the recording and monitoring of EC types.