GCCC 2578 Randomized Photon vs Proton RT for Newly Diagnosed Gynecologic Primaries

Inclusion Criteria: 1. a. Newly diagnosed endometrial cancer after TAH/BSO and nodal sampling, sentinel LN biopsy or pelvic nodal dissection planning to receive sequential chemotherapy and radiation or concurrent chemoradiotherapy or b. cervical cancer planning to receive definitive chemoradiation with HDR brachytherapy boost 2. Histologic confirmation of malignancy (primary only) 3. ≥ 18 years of age 4. ECOG performance status ≤ 2 5. Patient must have the ability to understand and the willingness to sign a written informed consent document or when appropriate, have an acceptable surrogate capable of giving consent on the subject's behalf. 6. Insurance approval for IMPT Exclusion Criteria: 1. Metastatic disease beyond para-aortic lymph nodal region 2. Residual tumor after surgery exceeding 2 cm in maximum dimension in patients with endometrial cancer. 3. FIGO 2014 stage III-IVA cervix cancer planning to receive concurrent pembrolizumab. 4. Cervical cancer with inability to receive concurrent chemotherapy. 5. Any prior pelvic radiation. 6. Treatment with other investigational agents. 7. Carcinosarcoma. 8. Creatine clearance \<30 mL/m2 9. Unable to lie flat during or tolerate radiation. 10. Refusal to sign informed consent. 11. Any additional active cancer that would interfere with the primary study endpoints