Feasibility of Dose Escalation Using Intraoperative Radiotherapy Following Resection of Large Brain Metastases Compared to Post-Operative Stereotactic Radiosurgery

Abstract

Dose reduction is used for increasing tumor volumes in stereotactic radiosurgery (SRS) due to risks of radiation injury reaction with increasing tumor diameter. This concept runs contrary to the general principles of oncology, where more tumor should not require less dose, and this may contribute to increases in local failure which approaches 40% in prospective studies for surgery followed by SRS. Thus alternative strategies are warranted. We hypothesize that the steep conformal fall off inherent to intra-operative radiotherapy (IORT) will afford dose escalation over SRS without increasing dose to critical structures.