Study Title

Phase I/II Trial of Pre-Operative Image Guided Intensity Modulated Proton Radiation Therapy (IMPT) or Photon (IMRT) with Simultaneously Integrated Boost to the High Margin for Retroperitoneal Sarcomas

Summary

The purpose of this study is to determine the highest dose of radiation therapy with protons or IMRT that can be delivered safely in patients with retroperitoneal sarcomas and the effectiveness of proton beam radiation therapy as an intervention for patients with retroperitoneal sarcomas.

Objective

Objectives: - For the Phase I portion of the study, to determine the maximum tolerated dose (MTD) of preoperative IG-IMPT and IMRT with simultaneously integrated boost to the high risk margin of retroperitoneal sarcoma. This is mainly based on evaluation of acute toxicity profile of each participant. - For the Phase II portion of the study, to determine the local control rate after the protocol treatment (IG-IMPT or IMRT MTD with simultaneously integrated boost to the high risk margin) followed by surgical resection.