Introduction:

Adjuvant radiation (aRT) for men with adverse pathologic features at radical prostatectomy has been associated with improved biochemical control in 3 previously published randomized controlled trials but the impact on survival remains unclear. With the recent publication new data, our objective was to reassess if aRT versus observation is associated with improved oncologic outcomes among these patients.

Methods:

We performed a systematic review and meta-analysis of randomized trials. The primary outcome was overall survival (OS) and secondary outcomes were metastasis-free survival (MFS), loco-regional recurrence-free survival (RFS), biochemical progression-free survival (bPFS), and adverse events. Data were summarized using forest plots and synthesized using a random-effects meta-analysis.

Results:

Based on 4 randomized trials including 2068 patients with a median follow-up of 8.7-12.6 years, no significant OS benefit was detected aRT versus observation, although it offered a consistent bPFS and local-RFS benefit. There is an uncertain MFS benefit with aRT, and the effect is largely driven by one trial (SWOG-8794) with a notable risk of bias. There was also a moderate risk of overtreatment, with 35-60% of patients being biochemical recurrence-free with observation alone. There was a greater risk of experiencing any adverse events and grade 3-4 adverse events affecting gastrointestinal, urinary, and erectile function with aRT versus observation. The number of adverse events per patients was also higher with aRT.

Conclusion:

Although there is a consistent bPFS and local-RFS benefit with aRT, there is no clear OS benefit and the MFS benefit is uncertain. There is a greater risk of adverse events and a risk of overtreatment with aRT. These data may be helpful in reassessing the relative merits and harms of aRT in the contemporary era where early salvage radiotherapy is an alternate option.

Funding: n/a