PACE-A Trial Results: SBRT vs. Prostatectomy in Localized Prostate Cancer

Stereotactic body radiotherapy matches the five-year disease control of radical prostatectomy in localized prostate cancer while significantly lowering urinary incontinence rates, according to trial findings presented at the 2026 American Society for Radiation Oncology Annual Meeting in Boston.

PACE-A Trial Compares SBRT with Radical Prostatectomy

Patients were randomly assigned between August 2012 and February 2022, with 60 assigned to surgery and 63 to SBRT. Investigators noted that treatment selection is frequently driven by expected functional outcomes, though randomized evidence directly comparing the efficacy of radical prostatectomy with SBRT has historically been lacking. The trial cohort had a median age of 65.5 years (IQR, 60.5–68.6), with the vast majority presenting with intermediate-risk disease (92%).

SBRT and Surgery Show Similar Biochemical Control Rates

At the five-year mark, biochemical-free failure rates reached 94.8 percent for the SBRT cohort compared with 94.1 percent for the radical prostatectomy group (with 5-year BCF-free rates cited as 95% with SBRT and 94% with prostatectomy in trial data). By eight years of follow-up, with a median follow-up of 8 years (IQR, 6.9–10.1), biochemical control rates stood at 91.2 percent for SBRT and 83.7 percent for surgery, an unadjusted hazard ratio of 0.48 (95% CI, 0.16 to 1.46; P = .18) that did not reach statistical significance. Thirteen BCF events occurred overall: 8 in the prostatectomy arm and 5 in the SBRT arm. “It is really important to remember that these men are not dying of prostate cancer, so it’s the functional outcomes that are crucial to these men,” van As noted during the presentation.

SBRT Patients Report Better Urinary Function than Surgery Patients

Significant differences emerged in patient-reported urinary function, with 48 percent of surgery patients (14 of 29 patients) reporting the use of at least one urinary pad daily at five years, compared with only 8 percent of patients who received SBRT (3 of 36 patients). One prostatectomy patient (3.6%, or 1 of 28 patients) reported a moderate or big bowel problem at 5 years versus none in the SBRT arm. When we reported this at 2 years, there was a significant difference between SBRT and prostatectomy—SBRT was slightly worse—but that appears to have disappeared by 5 years, van As explained. The randomized findings support SBRT as an effective non-surgical treatment option and there were low … rates of side effects in both arms. … I therefore think all patients who are considering a radical prostatectomy should be given information about SBRT before they make their treatment decisions, added Dr. Van As during an ASTRO press briefing. During the follow-up period, subsequent interventions included five patients in the prostatectomy arm receiving prostate bed radiotherapy and one patient in the SBRT arm undergoing salvage prostatectomy, alongside five total patients starting androgen deprivation therapy (3 in the surgical arm and 2 in the SBRT arm). Researchers continue to analyze long-term data from the broader PACE platform.

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