An Accelerated Radiotherapy Scheme Using a Concomitant Boost Technique for the Treatment of Unresectable Stage III Non-small Cell Lung Cancer

Abstract

We designed a phase II trial for evaluation of the efficacy and tolerability of an accelerated concomitant boost radiotherapy scheme for the treatment of the patients with non-small cell lung cancer (NSCLC). Thirty patients with unresectable stage IIIA/IIIB NSCLC were prospectively enrolled in this protocol. All patients were scheduled to receive 15 fractions of conventional radiotherapy in doses of 1.8 Gy, to a total of 27 Gy. For the last 10 treatment days, an accelerated concomitant boost schedule was started that was composed of 1.8 Gy/fraction/day, 5 days/week to the large field and 1.8 Gy/fraction/day to the boost field 6 h apart, to a total dose of 63 Gy/35 fractions/5 weeks. Median follow-up time was 13 months (range, 5-50 months; 3-year overall, disease-free, loco-regional disease-free and metastasis-free survivals were 23%, 19%, 19% and 23%, respectively). The most common acute toxicity was esophagitis in 31% of patients with the Radiation Therapy Oncology Group and the European Organization for Research and Treatment of Cancer (RTOG/EORTC) criteria grade 1, and in 54% with grade 2. Radiation pneumonitis developed in 16% of patients with RTOG/EORTC grade 1. Three-year actuarial rate of late pulmonary and skin-subcutaneous toxicity were 12% and 16%, respectively. No late radiotherapy complications of spinal cord or esophagus were recorded. Overall survival, local control and freedom from local progression were comparable with the results reported with pure hyperfractionated radiotherapy. The overall rate of acute and late toxicity was acceptable.