This is a retrospective chart review study. Medical records are reviewed and data collected through the hospital's electronic medical record (EMR). Participants are women that had definitive treatment for endometrial cancer between 2016-2020 at WellSpan York Hospital Department of Gynecologic Oncology. Participants are identified and their chart reviewed for demographic data of age, race, comorbid conditions, and use of metformin. Possible confounding information is documented, including chemotherapy status, radiotherapy status, cancer and tumor type, grade, and stage, available genetics information, medications at the time of cancer diagnosis, and medication durations. Those patients who had cancer recurrence are identified. Recurrence data including type, time interval, additional treatment are collected. Recurrence is defined as any recurrence validated by clinical, imaging and histological data and can be identified based on the cancer registry. Recurrence rate in participants that took metformin vs. those that did not is calculated. Time to endometrial cancer recurrence is calculated. Progression free survival and overall survival are calculated. Statistical analysis is performed to compare each of these outcomes between participants who took metformin vs. those that did not.
Given the early literature available and its biological plausibility as an inhibitor of the mammalian target of rapamycin (mTOR) protein, it is hypothesized that women with endometrial cancer who take metformin for non-cancer related reasons have a lower cancer recurrence rate compared to women not taking metformin. The primary goal of this study is to determine whether metformin use is associated with a decrease in the rate of endometrial cancer recurrence. Secondary objectives are to assess whether women with endometrial cancer taking metformin have longer progression free survival and overall survival than those that do not take metformin.