External-beam radiation therapy (EBRT)

A retrospective review of 999 patients treated with megavoltage radiation therapy showed that cause-specific survival rates at 10 years varied substantially by T stage: T1 (79%), T2 (66%), T3 (55%), and T4 (22%).[63] An initial serum PSA level higher than 15 ng/mL is a predictor of probable failure with conventional radiation therapy.[64]

Several randomized studies have demonstrated an improvement in freedom from biochemical (PSA-based) recurrence with higher doses of radiation therapy (74–79 Gy) as compared with lower doses (64–70 Gy).[65-69][Level of evidence B1] None of the studies demonstrated a cause-specific survival benefit to higher doses.

Several randomized studies have demonstrated an improvement in freedom from biochemical (PSA-based) recurrence with higher doses of radiation therapy (74–79 Gy) as compared with lower doses (64–70 Gy).[65-69][Level of evidence B1] None of the studies demonstrated a cause-specific survival benefit to higher doses.

The MRC-RT01 study (NCT00003290) enrolled 843 men with stage T1b through T3a, N0, M0 prostate cancer. Patients were randomly assigned to receive 64 Gy in 32 fractions versus 74 Gy in 37 fractions by conformal delivery.[68] Men in both study groups received neoadjuvant LH-RH agonist injections every 4 weeks for 3 to 6 months before the start of radiation therapy and throughout the radiation course. The study was powered to detect differences in both biochemical progression-free survival (PFS) and a 15% difference in overall survival (OS).

Several randomized studies have demonstrated an improvement in freedom from biochemical (PSA-based) recurrence with higher doses of radiation therapy (74–79 Gy) as compared with lower doses (64–70 Gy).[65-69][Level of evidence B1] None of the studies demonstrated a cause-specific survival benefit to higher doses.

After a median follow-up of 10 years, despite a statistically significant improvement in biochemical PFS with the higher dose of radiation, the 10-year OS rate was the same in both groups: 71% (HR, 0.99; 95% CI, 0.77–1.28; P = .96). Likewise, there were no differences in prostate—cancer-specific survival.

Several randomized studies have demonstrated an improvement in freedom from biochemical (PSA-based) recurrence with higher doses of radiation therapy (74–79 Gy) as compared with lower doses (64–70 Gy).[65-69][Level of evidence B1] None of the studies demonstrated a cause-specific survival benefit to higher doses.

Likewise, in the RTOG-0126 trial (NCT00033631), 1,532 men with stage cT1b to T2b (Gleason score 2 to 6 and PSA 10 to <20 ng/mL or Gleason score 7 and PSA <15 ng/mL) prostate cancer were randomly assigned to receive 79.2 Gy in 44 fractions compared with 70.2 Gy in 39 fractions (using 3D conformal or intensity-modulated radiation therapy [IMRT]).[69] With a median follow-up of 8.4 years (maximum, 13.0 years), 8-year OS rates were 76% and 75% (HR, 1.00; 95% CI, 0.83–1.20; P = .98). However, the high-dose radiation was associated with increased late-grade 2 or greater gastrointestinal and genitourinary toxicities (21% and 12% with 79.2 Gy and 15% and 7% with 70.2 Gy).