From 1994 to 1999, we conducted a phase I/II clinical trial for stage I non-small cell lung cancer (NSCLC) by using carbon ion beams alone, demonstrating optimal doses of 90.0GyE in 18 fractions over 6 weeks (Protocol #9303) and 72.0GyE in 9 fractions over 3 weeks ( #9701) for achieving more than 95% local control with minimal pulmonary damage. In the present study, the total dose was fixed at 72.0GyE in 9 fractions over 3 weeks (#9802), and at 52.8GyE for stage IA and 60.0GyE for stage 1B in 4 fractions in 1 week (#0001). Following this schedule, we conducted a phase II clinical trial for stage I NSCLC from 1999 to 2003. We also conducted a phase I/II single fractionation clinical trial (#0201), a dose escalation study. The total dose was initially 28.0GyE in 2003, and it was raised to 50.0GyE in 2011. The local control rate for all patients (#9802 and #0001) was 91.5%, and those for T1 and T2 tumors were 96.3% and 84.7%, respectively. The 5-year cause-specific survival rate was 67.0% (IA: 84.4, IB: 43.7), and overall survival was 45.3% (IA: 53.9, 1B: 34.2). No adverse effects greater than grade 2 occurred in the lung. In a single fractionation trial, the 5-year local control rate for 151 patients was 79.2%, and the control rates for T1 and T2 tumors were 83.6% and 72.2%, respectively. No adverse effects greater than grade 2 occurred in the lung. Carbon beam radiotherapy, an excellent new modality in terms of high QOL and ADL, was proven to be a valid alternative to surgery for stage I cancer, especially for elderly and inoperable patients.Heavy Ion in Therapy and Space Radiation Symposium 2013(HITSRS2013
