Long-term outcomes for men with high-risk prostate cancer treated definitively with external beam radiotherapy with or without androgen deprivation
See editorial on pages 3260–3261, this issue.
Men with high-risk prostate cancer are often thought to have very poor outcomes in terms of disease control and survival even after definitive treatment. However, results after external beam radiotherapy have improved significantly through dose escalation and the use of androgen deprivation therapy (ADT). This report describes long-term findings after low-dose (< 75.6 Gy) or high-dose (≥ 75.6 Gy) external beam radiation, with or without ADT.
This analysis included 741 men with high-risk prostate cancer (clinical classification ≥ T3, Gleason score ≥ 8, or prostate-specific antigen level ≥ 20 ng/mL) treated with external beam radiotherapy at a single tertiary institution from 1987 through 2004. The radiation dose ranged from 60 to 79.3 Gy (median, 70 Gy); 295 men had received ADT for ≥ 2 years, and the median follow-up time was 8.3 years.
The 5- and 10-year actuarial overall survival rates were significantly better for men treated with the higher radiation dose (no ADT plus ≥ 75.6 Gy, 87.3% and 72.0%, respectively; and ADT plus ≥ 75.6 Gy, 92.3% and 72%, respectively) (P = .0035). The corresponding 5- and 10-year biochemical failure-free survival rates were significantly better for patients treated with both ADT and higher radiation dose (82% and 77%, P < .0001). At 5 years, men who had not received ADT and had received radiation dose < 75.6 Gy had higher clinical local failure rates than those given ADT and radiation dose ≥ 75.6 Gy (24.2% versus 0%, P < .0001). The 10-year symptomatic local failure rate was only 2% for all patients.
Contrary to lingering historical perceptions, treatment of high-risk prostate cancer with modern, high-dose, external beam radiotherapy and ADT can produce better biochemical, clinical, and survival outcomes over those from previous eras. Specifically, symptomatic local failure is uncommon, and few men die of prostate cancer even 10 or more years after treatment. Cancer 2013;119:3265–71. © 2013 American Cancer Society.