Prostate cancer continues to pose a significant challenge for both patients and healthcare providers. In the realm of radiation therapy, the development of advanced techniques has transformed the landscape of treatment. A recent phase 3 trial comparing Stereotactic Body Radiotherapy (SBRT) to conventional radiotherapy for intermediate-risk prostate cancer provides new insights into how we can deliver effective cancer treatment with fewer treatment sessions while maintaining efficacy and safety.
What Is SBRT and How Does It Compare?
SBRT is an advanced form of radiotherapy that allows high doses of radiation to be delivered with pinpoint precision in just a few treatment sessions. Traditionally, patients with intermediate-risk prostate cancer have undergone conventional or moderately hypofractionated radiotherapy, which requires up to 39 sessions over several weeks. In contrast, SBRTcondenses this into just 5 fractions, typically over the course of 1 to 2 weeks.
The PACE-B trial, conducted across multiple international centers, directly compared the outcomes of patients receiving SBRT to those undergoing conventional radiotherapy. The trial included 874 men with localized prostate cancer, with the majority having intermediate-risk disease. The study aimed to determine whether SBRT could match the efficacy of conventional treatment in preventing biochemical or clinical failure while offering the convenience of fewer sessions.
Key Findings from the Trial
At a median follow-up of 74 months, the results were promising:
- Biochemical or Clinical Failure Rates: The 5-year rate of freedom from biochemical or clinical failure was 95.8% for SBRT and 94.6% for conventional radiotherapy, demonstrating the noninferiority of SBRT. In other words, the shorter treatment was just as effective at controlling the cancer as the longer, more conventional approach.
- Toxicity and Side Effects: Although SBRT was found to have a slightly higher incidence of genitourinary toxic effects (such as urinary issues), the overall rate of late-term gastrointestinal toxic effects was similar between both groups, indicating that SBRT remains a safe and viable option for most patients.
The Benefits of SBRT
- Fewer Treatment Sessions: For patients, fewer treatment sessions mean less disruption to daily life, fewer hospital visits, and reduced socioeconomic and psychological burdens.
- Noninferior Efficacy: SBRT matches the cancer-control rates of conventional therapy, offering peace of mind without the prolonged schedule.
- Reduced Healthcare Burden: As healthcare systems manage increasing demands, treatments like SBRT that reduce overall treatment time can help free up resources without compromising patient outcomes.
Patient Selection and Counseling
While the results of this trial highlight SBRT as a robust alternative for many patients, not everyone may be suited for this treatment. Patients with significant urinary symptoms at baseline may experience higher rates of long-term side effects with SBRT. Therefore, proper patient selection, thorough counseling, and ongoing monitoring are critical to achieving the best outcomes.
A Shift in Standard Care?
The findings from the PACE-B trial suggest that SBRT could become a standard of care option for patients with intermediate-risk prostate cancer. Its convenience, coupled with similar efficacy to conventional approaches, offers a win-win for both patients and providers. As radiation therapy continues to evolve, SBRT provides a glimpse into the future of cancer treatment—one that prioritizes both efficacy and quality of life.
About the author
Dr. Daniel Landau is a distinguished board-certified hematologist/oncologist renowned for his exceptional contributions in the field. With an illustrious career spanning across esteemed institutions like the Orlando Health Cancer Institute and the Medical University of South Carolina, Dr. Landau’s expertise shines in both genitourinary oncology and hematology. .
Engage with Dr. Landau’s expertise and ignite your curiosity on “Ask MedOnCMD” as he invites you to explore the vast landscape of oncology with a fresh outlook.