MRI-guided focused ultrasound destroys prostate cancer tissue with minimal side effects

MRI-guided focused ultrasound effectively kills prostate cancer tissue with few negative side effects, according to a new study published in Radiology.

Nearly 1 in 8 men will be diagnosed with prostate cancer during his lifetime, making it the most common form of the disease outside of non-melanoma skin cancers. In this study, nearly all patients treated with high-intensity focused ultrasound, however, were disease-free at their treatment site after a five-month follow-up biopsy.

The technique is still pending U.S. Food & Drug Administration approval, but if that hurdle is cleared, MRgFUS may be a promising option for intermediate-risk patients’ looking to preserve their quality of life, principal investigator Sangeet Ghai, MD, explained Tuesday.

“The results so far have been very good," Ghai, with Toronto’s Joint Department of Medical Imaging, explained in a statement. "We treated a smaller area using this device, yet still had very good results. At the same time, the patients preserved their erectile and urinary function."

For their prospective phase 2 trial, the researchers performed MRI-informed high-intensity focused ultrasound in 44 men with prostate cancer between February 2016 and July 2019. They tracked the success of the four-hour procedure using MRI, biopsies, and surveys on erectile and urinary function.

The procedure was successfully completed in all participants, with no major adverse events. Furthermore, five-month follow-up showed 41 or 93% of men were cancer-free at their area of treatment. Erectile function and prostate symptom scores were similar at the same follow-up time.

Using MRgFUS is more expensive and requires an expert operator, the group noted, but comes with unique advantages, including almost instant thermal feedback during treatment to increase the chances of destroying cancerous tissue.

In an editorial published alongside Ghai and colleagues’ study, a Brigham and Women’s Hospital radiologist said the findings are an “important step forward” in noninvasive prostate cancer treatment.

Clare M. C. Tempany-Afdhal, MD, did point out that the technique still faces an uphill regulatory battle.

“The road to full acceptance of this innovative approach remains challenging, with phase 3 trials and U.S. Food and Drug Administration, Centers for Medicare and Medicaid Services, and payor approvals all ahead,” she added Tuesday.