A Dosimetric Pilot Study on the Feasibility of the Dosimetric Compliance Criteria of RTOG 1308: Phase III Randomized Trial Comparing Overall Survival After Photon Versus Proton Radiochemotherapy for Inoperable Stage II-IIIB NSCLC

Abstract

RTOG 1308 is a phase III randomized trial comparing overall survival after photon versus proton chemoradiation therapy for inoperable stage II-IIIB NSCLC, to determine if proton therapy can improve overall survival by reducing the risk of severe toxicity to organs at risk compared to photon-based IMRT. More stringent dose constraints are being used for RTOG 1308 than prior NSCLC RTOG studies. The purpose of this work is to establish the feasibility of the dosimetric criteria of this trial through testing against photon IMRT and passively scattered proton therapy (PSPT) plans and to assess the effect of different definitions of normal lungs (lungs minus GTV (DVHG), lungs minus CTV (DVHC) and lungs minus PTV (DVHP)) on lungs dose parameters.