Executive summary

Published in the Green Journal, this study by MD Anderson group reported clinical outcomes of 2772 patients with localized prostate cancer treated with proton therapy to a total dose of 78 Gy in 1.8-2.0 Gy(RBE) fractions. For this cohort of patients which included low [LR, n = 640]; favorable-intermediate [F-IR, n = 850]; unfavorable-intermediate [U-IR, n = 851]; high [HR, n = 315]; and very high [VHR, n = 116], freedom from biochemical relapse (FFBR) rates at 5 years and 10 years were 98.2% and 96.8% for the LR group; 98.3% and 93.6%, F-IR; 94.2% and 90.2%, U-IR; 94.3% and 85.2%, HR; and 86.1% and 68.5%, VHR. Two patients died of prostate cancer. Overall rates of late grade ≥ 3 GU and GI toxicity were 0.87% and 1.01%. The authors concluded that proton therapy demonstrated excellent clinical outcomes, even among higher-risk groups with historically poor outcomes despite aggressive therapy.