An updated efficacy analysis of the international phase III PACE-A trial showed high rates of freedom from biochemical or clinical failure (BCF) with both stereotactic body radiation therapy (SBRT) and radical prostatectomy in patients with localized prostate cancer, with no statistically significant difference between treatment arms, as reported at the 2026 American Society for Radiation Oncology (ASTRO) Annual Meeting.1
“Patients diagnosed with localized prostate cancer have long had to choose between surgery and radiation therapy without randomized evidence directly comparing the treatments, [but] PACE-A changes that…,” presenting author and principal investigator Nicholas van As, MD, of The Royal Marsden NHS Foundation Trust, London, explained in a news release issued by ASTRO.
Nicholas van As, MD
Beyond cancer control, the updated analysis showed that previously observed benefit in urinary function with SBRT persisted with longer follow-up, while a separate PACE-A report presented at the same meeting demonstrated continued differences in sexual function favoring SBRT.1,2 “That gives patients a much fuller picture of what to expect from each treatment,” Dr. van As remarked.
He said that, taken together, the findings support SBRT as an effective nonsurgical option and that all patients considering radical prostatectomy should receive information about SBRT before making a treatment decision.
Study Details
The international, randomized controlled phase III PACE-A trial enrolled 123 patients with localized prostate cancer from eight centers in the United Kingdom who were randomly assigned to undergo surgery or five-treatment SBRT. Hormone therapy was not allowed in the study. Patients were followed for a median of 8 years.
At a median follow-up of 8 years, biochemical/clinical failure occurred in five patients assigned to SBRT and eight patients assigned to prostatectomy (HR = 0.48, 95% CI = 0.16–1.46; P = .18). Based on the hazard ratio, the estimated absolute difference in BCF-free survival at 5 years was 3.1 percentage points (95% CI = –2.6 to 5.0). The 5-year BCF-free rates were 94.8% with SBRT and 94.1% with prostatectomy.
“The numbers favor SBRT, but there were too few cancer events to conclude that it was superior,” Dr. van As said. “What we can say is that we saw very few cancer failures in either group, and that we have mature data showing excellent cancer outcomes with five-treatment radiotherapy.”
Several patients required subsequent treatment for progression, including one patient in the SBRT arm who underwent surgery and two who received androgen-deprivation therapy, and five patients in the prostatectomy arm who underwent radiotherapy and three who received androgen-deprivation therapy.
Patient-reported outcomes revealed that at 5 years, 8.3% of patients in the SBRT arm used at least one urinary pad as well as 48% of patients in the prostatectomy arm. Additionally, 0% of patients in the SBRT compared to 3.6% of patients in the prostatectomy arms, had moderate to large bowel function problems.
In a separate presentation at the 2026 ASTRO Annual Meeting, researchers also noted that although sexual function scores declined in both treatment arms, scores were higher in the SBRT arm.2
“We now have longer-term information on both cancer control and the functional outcomes that matter greatly to patients,” Dr. van As said. “The urinary and sexual-function benefits seen at two years remained evident at 5 years, while cancer control remained excellent through longer follow-up. That gives patients a much fuller picture of what to expect from each treatment.”
Genitourinary adverse events of grade 2 or higher were reported in 3.8% of patients in the radiation arm and in 2.5% of those in the surgery arm.
DISCLOSURE: Dr. van As reported no conflicts of interest.
REFERENCES
1. van As N, Patel J, Tree A, et al: Efficacy of radical prostatectomy versus stereotactic body Radiotherapy (SBRT) for localised prostate cancer: Results from an international phase III randomised controlled trial (PACE - A). Abstract LBA32. ASTRO Annual Meeting. Presented September 28, 2026.
2. Yasar B, Patel J, Tree A, van As N (presenter), et al: Long-term outcomes of sexual function in the PACE-A trial: A multicentre randomised study of radical prostatectomy vs stereotactic body radiotherapy (SBRT) for early localised prostate cancer. Abstract LBA10. ASTRO Annual Meeting. Presented September 29, 2026.
EXPERT POINT OF VIEW
In an interview with The ASCO Post, Amar U. Kishan, MD, Chair of the ASTRO Genitourinary Cancer Resource Panel and Executive Vice Chair for the Department of Radiation Oncology at the David Geffen School of Medicine at the University of California, Los Angeles (UCLA) and the UCLA Jonsson Comprehensive Cancer Center, commented on the updated results of the PACE-A trial.1,2
“For patients with localized prostate cancer, particularly those with a highly favorable prognosis, the main goal of any definitive treatment should be to maintain efficacy while optimizing patient quality of life during survivorship. Specifically, any radical treatment—radical prostatectomy or definitive radiotherapy—can impact urinary, bowel, and sexual function. Since men with prostate cancer live many years after definitive treatment, it is important to minimize the adverse impact that any treatment can have.
Amar U. Kishan, MD
“The only published randomized comparative trial to report on both efficacy and quality of life after treatment is the ProtecT trial, which randomly assigned 1,643 men to active monitoring, radical prostatectomy, and radical radiotherapy with 6 months of androgen-deprivation therapy. Briefly, 15-year prostate cancer mortality was approximately 3% or less in all three arms, while urinary pad usage through 12 years was lower with radiotherapy than prostatectomy, and erections sufficient for intercourse were preserved longer with radiotherapy.3,4 The 12-year fecal leakage, on the other hand, was higher with radiotherapy.4 However, this trial enrolled patients from 1999 to 2009, and a critique has been that both the surgical strategy and the radiotherapy strategy are outdated, making it difficult to extrapolate these outcomes to patients coming to clinic for counseling in 2026.
“The PACE-A trial fills this evidence gap. This trial randomly assigned 123 men to prostatectomy (predominantly robot-assist) vs stereotactic body radiotherapy (SBRT); accrual proceeded between 2012 and 2022, so this captured more modern approaches to therapy. The main takeaways from the study are reinforcing the oncologic equivalency of these two treatments through a median of 8 years of follow-up and addressing the abovementioned criticism of the ProtecT quality-of-life data.
“With more modern approaches used for both surgery and radiotherapy, we see an overall confirmation of the differences in urinary incontinence and sexual function observed in ProtecT. On the other hand, potentially speaking to significant improvements in radiotherapy technology, we see no evidence of difference in patient-reported bowel bother in PACE-A.
“These data are important in underscoring that both surgery and radiotherapy are standard-of-care options for the definitive treatment of localized prostate cancer, and patients should be informed of the outcomes of both so that informed decisions can be made by patients and their loved ones.”
DISCLOSURE: Dr. Kishan has received grant support from the National Institutes of Health and the U.S. Department of Defense; has contracts with Novartis, Janssen, Lantheus, Varian Medical Systems, and ViewRay Systems; has received consulting fees from Lantheus, Varian Medical Systems, Novartis, and Janssen; has received honoraria from Janssen, Boston Scientific, Varian Medical Systems, and Lantheus; and reported holding low-value stock in MiraDx and Alethian AI.
REFERENCES
1. van As N, Patel J, Tree A, et al: Efficacy of radical prostatectomy versus stereotactic body Radiotherapy (SBRT) for localised prostate cancer: Results from an international phase III randomised controlled trial (PACE - A). Abstract LBA32. ASTRO Annual Meeting. Presented September 28, 2026.
2. Yasar B, Patel J, Tree A, van As N (presenter), et al: Long-term outcomes of sexual function in the PACE-A trial: A multicentre randomised study of radical prostatectomy vs stereotactic body radiotherapy (SBRT) for early localised prostate cancer. Abstract LBA10. ASTRO Annual Meeting. Presented September 29, 2026.
3. Hamdy FC, Donovan JL, Lane JA, et al: Fifteen-year outcomes after monitoring, surgery, or radiotherapy for prostate cancer. N Engl J Med 388:1547-1558, 2023.
4. Donovan JL, Hamdy FC, Lane JA, et al: Patient-reported outcomes 12 years after localized prostate cancer treatment. NEJM Evid 2: 2023. Available at https://evidence.nejm.org/doi/full/10.1056/EVIDoa2300018. Accessed October 27, 2026.
