MRI-guided SBRT reduces side effects of prostate cancer treatment

Results

After a comprehensive two-year follow-up, researchers at UCLA Health Jonsson Comprehensive Cancer Center found that MRI-guided stereotactic body radiotherapy (SBRT) for prostate cancer significantly reduced long-term side effects and improved quality of life , particularly in the intestine and cancer. sexual health, compared to conventional CT-guided treatment.

The MIRAGE trial is the only randomized trial to date comparing these cutting-edge technologies in radiation oncology. It was designed to see if MRI-guided SBRT resulted in less toxicity than CT-guided SBRT.

Dr. Michael Steinberg, professor and chair of radiation oncology at the David Geffen School of Medicine at UCLA, director of clinical affairs at the UCLA Health Jonsson Comprehensive Cancer Center and senior author of the study

Background

The research team conducted a secondary analysis of the Phase 3 clinical trial, called MIRAGE, to evaluate the impact of using MRI guidance to deliver high-precision radiotherapy for prostate cancer. Radiation therapy is a standard treatment option, especially for people with localized prostate cancer. However, side effects of treatment can be serious and long-lasting, affecting the patient’s urinary, bowel, and sexual function. MRI guidance allows for more targeted treatment with reduced planning margins around the prostate, meaning less exposure to surrounding healthy tissue. This approach was compared to standard CT-guided SBRT, which typically requires larger treatment margins.

Results

The team found that patients receiving MRI-guided SBRT had significantly fewer urinary and bowel side effects. Specifically, 27% of MRI-guided patients reported moderate or severe urinary problems, such as urinary incontinence and irritation, compared to 51% of those receiving CT guidance. Additionally, gastrointestinal toxicity, such as intestinal problems, was reported by only 1.4% of MRI-guided patients, a notable reduction from 9.5% in the CT-guided group. MRI guidance was also correlated with better scores on specific quality of life measures, including bowel function and sexual health.

Impact

The findings highlight a promising shift in prostate cancer treatment practices, highlighting the potential of MRI-guided radiotherapy to improve patient outcomes.

“This study adds strong evidence that the improved precision and accuracy offered by MRI-guided SBRT results in significantly fewer urinary, bowel, and sexual side effects in men receiving prostate SBRT,” noted Dr. Amar Kishan, executive vice chair of radiation oncology at the David Geffen School of Medicine at UCLA and first author of the study. “The MRI-guided approach, which includes real-time monitoring of the prostate itself and the use of an integrated MRI to help deliver the radiation, allows us to use significantly narrower planning margins when of radiation administration, which leads to less radiation compared to normal tissues. This in turn reduces the risk of lasting side effects that can impact a patient’s quality of life.

Newspaper

The study was published in the journal European Urology and presented earlier this year at the American Society for Radiation Oncology (ASTRO) meeting in Washington DC.

Authors

Other UCLA authors include James Lamb, Holly Wilhalme, Maria Casado, Natalie Chong, Lily Zello, Jesus Juarez, Tommy Jiang, Beth Neilsen, Daniel Low, Yingli Yang, John Neylon, Vincent Basehart, Luca Valle and Minsong Cao.