ABSTRACT
INTRODUCTION: This phase I/II trial was designed to determine the maximally tolerated dose of thoracic radiotherapy as part of a combined modality approach. This report includes the long-term outcomes of patients treated on this study. The phase II portion was never completed, as RTOG-0617 opened before it was concluded. METHODS: In this study, the maximally tolerated dose was defined as 74 Gy of radiation in 37 fractions. Twenty-five patients with unresectable NSCLC were treated with 2-Gy daily fractions and concurrent weekly carboplatin and paclitaxel. Of these patients, 20 had stage III disease and five had stage I or II disease. RESULTS: Patients were followed until death or for a minimum of 5 years in the case of survivors. The median and 5-year survivals were 42.5 months and 20% for all patients, 52.9 months and 40% in patients with stages I or II disease, and 39.8 months and 15% in patients with stage III disease. CONCLUSIONS: The median survival of the stage III patients was quite favorable. We believe that this may have been due to a robust central review program of radiotherapy plans before treatment, ensuring compliance with protocol guidelines along with very low exposure of the heart to radiotherapy. Further improvements in 5-year survival will likely require research on both systemic therapy and thoracic radiotherapy. Potential therapeutic modalities that may aid in these efforts include immunotherapy, targeted therapy, improved imaging, adaptive radiotherapy, simultaneous integrated boost techniques, novel dose fractionation regimens, and charged particle therapy.
