Indications for Radiation Therapy After Robotic-Assisted Radical Prostatectomy

Adjuvant Radiation Therapy Indications

The National Comprehensive Cancer Network recommends adjuvant radiotherapy for patients with seminal vesicle invasion, positive surgical margins, and extraprostatic extension due to demonstrated reductions in biochemical recurrence, local recurrence, and clinical progression 1, 2
Adjuvant radiotherapy is indicated for patients with positive surgical margins, especially if diffuse (>10 mm margin involvement or ≥3 sites of positivity) 3, 4
The National Comprehensive Cancer Network recommends adjuvant radiotherapy for patients with extraprostatic extension 1, 2
Adjuvant radiotherapy is indicated for patients with pathologic T3 disease 3, 2
The National Comprehensive Cancer Network recommends adjuvant radiotherapy for patients with Gleason score 8-10 5
Adjuvant radiotherapy is indicated for patients with short PSA doubling time (<9 months) 3, 6

Salvage radiotherapy is indicated when there is evidence of disease recurrence after surgery, including biochemical recurrence (PSA ≥0.2 ng/mL with a second confirmatory level ≥0.2 ng/mL) 7, 8
The National Comprehensive Cancer Network recommends salvage radiotherapy for patients with detectable PSA that increases on two subsequent measurements 5
Salvage radiotherapy is indicated for patients with local recurrence with no evidence of distant metastatic disease 1, 4

The SWOG 8794 trial demonstrated that adjuvant RT reduced PSA relapse and disease recurrence with improved 10-year biochemical failure-free survival for high-risk patients (36% vs 12% for observation; p=.001) 3, 2
The EORTC trial showed that 5-year biochemical progression-free survival significantly improved with RT compared to observation for patients with positive surgical margins (78% vs 49%) 3, 2
A German study by Wiegel et al. found that postoperative radiation improved 5-year biochemical progression-free survival compared to observation alone (72% vs 54%; HR, 0.53) 3, 2

The National Comprehensive Cancer Network recommends prescribed doses of 64-70 Gy in standard fractionation 5
The minimum dose should be 64-65 Gy 7, 8
Target volumes include the prostate bed 3, 5
Pelvic lymph nodes may be irradiated, but pelvic radiation is not necessary in most cases 3, 5

The National Comprehensive Cancer Network recommends ADT (category 1 option) for patients with positive lymph nodes 3, 2
Observation (category 2A for very low-risk or low-risk patients; category 2B for intermediate, high, or very high-risk patients) is also an option for patients with positive lymph nodes 3, 2
The addition of pelvic RT to ADT (category 2B) may be considered for patients with positive lymph nodes 3, 2