External beam management of stage I and II uterine cancer

This review article highlights the treatment paradigms for early-stage endometrial cancer with a focus on the role of external beam radiation therapy. We aim for this review to serve as an introductory resource for gynecological oncologists, radiation oncologists, medical oncologists, and other practitioners to understand the treatments for this disease. The main treatment of endometrial cancer is surgical resection with total hysterectomy and bilateral salpingo-oophorectomy. The benefit of adjuvant radiation after surgery is primarily to prevent local recurrence. Patients with low risk of recurrence can be observed post-operatively. Vaginal cuff brachytherapy, which has been shown to be equally effective as pelvic radiation with fewer side effects, is typically recommended for high-intermediate risk patients (with characteristics such as lymphovascular space invasion, high grade, or significant myometrial invasion). In the adjuvant setting, pelvic radiation therapy is reserved for patients who have deeply invasive stage I grade 2 or 3 disease, stage II disease, and non-endometrioid histologies. In patients who are not medically operable, definitive treatment consists of brachytherapy±pelvic external beam radiation therapy. We have highlighted the main acute and long-term side effects of pelvic radiation as well as recommendations for symptom management and summarized promising evidence showing improved rates of toxicities with more conformal radiation techniques.