Abstract 985: Assessment of obesity and lifestyle risk factors and endometrial cancer stage

Abstract Introduction: Obesity is a potentially modifiable risk factor for endometrial cancer (EC), and women with higher levels of obesity have been shown to have less aggressive disease stage and histology of EC. Issues still remain, however, as to whether BMI is an independent risk factor for EC stage, or if it is affected by other factors, such as tumor grade, race, age, and other lifestyle factors, including diet and physical activity. High-fat and high glycemic index diets have been shown to increase EC risk versus diets high in fruit/vegetable consumption, but links between diet and EC stage have not been established. Similarly, light or moderate levels of physical activity have also shown a reduced risk of EC but associations with stage have not been established. This study sought to examine the effect of BMI and other risk factors, such as age, race, grade, diet and physical activity on EC stage. Methods: Participants were women from 3 hospitals (The Ohio State University, Walter Reed Army Medical Center/Washington Hospital, and Duke University Medical Center), with suspected EC prior to surgery. Demographic and anthropometric data were obtained from patient medical records; diet and physical activity were assessed with validated food frequency and physical activity questionnaires used in the Women's Health Initiative. Logistic regression models were developed to assess the effect of BMI and other risk factors on late versus early EC stage. Summary: Of 129 participants, the mean age was 59 years (median=60), over 68% had a BMI>30 (median=35), and 85% of women were white. The majority of women (78%) were in early EC stages (1/2 vs 3/4) and 62% had a well differentiated versus a moderately or poorly differentiated tumor grade. Logistic regression analyses showed a significant association between BMI and late versus early EC stage in univariate models (OR=0.28, p=0.026), but was not significant when adjusting for both grade and age in the final model. Higher grade was significantly associated with later versus early EC stage (OR=4.08, p=0.015) when controlling for BMI and age. No associations with EC stage were shown for race, diet (fat, fruit/vegetable consumption, glycemic load) or physical activity expenditure. Conclusion: The results show that although BMI was not significantly associated with being in late versus early EC stage when adjusting for both age and grade. Therefore, BMI was not independently associated with EC stage in this study. Tumor grade showed a significant 4-fold increased odds of being in late versus early EC stage. Age showed marginal significance in the bivariate and final models, but may have confounded the effect of BMI. Future studies should confirm these findings in larger, more diverse populations, as well as the effect of modifiable risk factors, such as diet and lifestyle factors on late versus early EC stage. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 985.