Yates MS, et al. - Authors sought to assess the impact of metformin or lifestyle intervention on endometrial proliferation in postmenopausal obese women, as well as to evaluate obesity-related biomarkers and the adverse events experienced. Researchers observed that metformin and lifestyle intervention produced minor changes to serum biomarkers, however lifestyle intervention produced significant weight loss and reduction in body fat. There is a need for improved biomarkers in order to stratify risk and test prevention strategies, particularly at the endometrial tissue level, given that obese postmenopausal women are at increased risk for endometrial cancer.