Comparison of Toxicities Between Proton Therapy and IMRT for Post Operative Treatment of Endometrial or Cervical Cancers.

Inclusion Criteria: Age ≥ 18 years Histologically confirmed diagnosis of cervical or endometrial cancer Musthave undergone an open or robotic hysterectomy (total abdominal, vaginal, radical, or totallaparoscopic) for carcinoma of the cervix or endometrium History and physical prior toregistration Documentation of history of:

• Smoking status
• Pelvic infection
• Pelvic Inflammatory Disease
• Endometriosis Planned to receive either proton or IMRT radiation treatment, with use of rectal balloon,at an IRB-approved Mayo Clinic site Plan for RT to pelvis with or without para-aortic lymph node irradiation. If received high-dose chemotherapy prior to registration, last dose must have been given

≥ 21 days prior to start of RT CBC performed within 21 days prior to registration. CT, MRI, PET/CT, or PET/MRI for staging before registration; may be pre-op or post-op ECOG Performance Score (Appendix B) 0-2 Provide written informed consent Willing to complete QOL questionnaires

Exclusion Criteria: Receiving external beam boost dose during RT Distant metastases Gross disease at time of RT Histology of endometrial stromal sarcoma, leiomyosarcoma, melanoma or small cellcarcinomas. Patients who exceed the weight/size limits of the treatment table Patients with active and/or inflammatory irritable bowel disease Positive or close surgical margins (≤ 3 mm) Prior RT to the pelvis Planned to receive inguinal node RT Hepatic insufficiency resulting in clinical jaundice and/or coagulation defects. Acquired Immune Deficiency Syndrome (AIDS) based upon current CDC definition; note that HIVtesting is not required for entry into this protocol. The need to exclude patients withAIDS from this protocol is necessary because the treatments involved in this protocol maybe immunosuppressive. Prior invasive malignancy (except non-melanomatous skin cancer) unless disease free for aminimum of 3 years Severe, active co-morbidity defined as follows:

• Unstable angina and/or congestive heart failure requiring hospitalization within thelast 6 months
• Transmural myocardial infarction within the last 6 months Acute bacterial or fungal infection requiring intravenous antibiotics at the time ofregistration Other major medical illness which requires hospitalization or precludes study therapy atthe time of registration Patients unwilling to have rectal balloon placed on a daily basis during RT