A recent phase 3 trial has demonstrated that stereotactic body radiotherapy (SBRT) is a viable treatment for localised prostate cancer, showing noninferior results compared to conventional radiotherapy regimens. This international study provides new evidence that SBRT, administered in just five sessions, offers an effective alternative for men with low- to intermediate-risk prostate cancer, potentially simplifying and shortening the treatment journey.
The trial, conducted across 38 centres, included 874 men with stage T1 or T2 prostate cancer, Gleason scores of 3+4 or lower, and prostate-specific antigen (PSA) levels under 20 ng/mL. Patients were randomly assigned to receive either SBRT (36.25 Gy over five sessions across one to two weeks) or conventional radiotherapy (78 Gy over 39 sessions in 7.5 weeks or 62 Gy over 20 sessions in 4 weeks). Androgen-deprivation therapy was not allowed, focusing solely on the impact of radiotherapy.
After a median follow-up of over six years, the results were promising. The five-year rate of freedom from biochemical or clinical failure was 95.8% in the SBRT group, slightly higher than the 94.6% in the conventional radiotherapy group, confirming SBRT’s noninferiority. However, while SBRT proved as effective in preventing cancer progression, it was associated with a higher rate of genitourinary side effects. Late-stage urinary side effects of grade 2 or higher occurred in 26.9% of SBRT patients compared to 18.3% in the conventional group, while gastrointestinal side effects were similar across both groups.
These findings suggest that SBRT may be a beneficial option for patients seeking a shorter treatment period, though clinicians must weigh the potential for increased urinary side effects. The study contributes valuable insights into prostate cancer care, providing patients with an alternative radiotherapy approach that balances effectiveness with a condensed treatment schedule.
Reference
van As N et al. Phase 3 Trial of Stereotactic Body Radiotherapy in Localized Prostate Cancer. New Engl J Med. 2024;391(15):1413-25.
