Each year about 150,000 men in North America are diagnosed with localized prostate cancer or disease that has not spread beyond the prostate. Sunnybrook researchers hope to help many of these individuals who would be eligible for a promising, new, minimally invasive treatment option called MRI-controlled transurethral ultrasound therapy.
This potential treatment uses high-intensity ultrasound energy guided and controlled by MRI (magnetic resonance imaging) and delivered via a unique system developed by Drs. Michael Bronskill, and Rajiv Chopra, scientists in the Physical Sciences platform at Sunnybrook Research Institute.
The research also involves the collaboration of Dr. Laurence Klotz, a surgical oncologist of the Genitourinary Cancer Care team at Sunnybrook's Odette Cancer Centre.
Preclinical and early clinical studies show the system's accuracy in the treatment of targets in the prostate to be within 1-3 millimeters. This accuracy suggests strong potential to minimize side effects such as reduced urinary, bowel and erectile function often associated with more radical radiation and surgical treatment options for localized prostate cancer. The researchers are planning to start clinical trials this summer evaluating the ability of this technology to eradicate tumours within the prostate gland.
“It’s like destroying cancerous prostate tissue with a thermal scalpel, while saving surrounding tissue and critical structures,” says Dr. Laurence Klotz, surgical oncologist of the Genitourinary Cancer Care team.
Dr. Klotz is now leading a Phase I clinical trial in collaboration with Dr. Chopra, Sunnybrook pathologist Dr. Linda Sugar who has subspecialties in genitourinary and renal pathology, and Dr. Masoom Haider, associate scientist, Physical Sciences platform, Sunnybrook Research Institute. The innovation behind this research was recently recognized internationally, and the team received a grant from the National Institutes of Health.
Sunnybrook has licensed this technology to Profound Medical Inc.
During the procedure, the patient lies in an MR imager that produces images every few seconds of the heat generated by the ultrasound energy. The heat destroys the targeted tissue within the prostate and the MR-temperature monitoring enables control and adjustment as the treatment is being delivered. The treatment itself takes about 30 minutes, and this minimally invasive approach shows strong promise for faster recovery time for patients.
"The procedure is quick. It's precise. There's no incision. We hope it will preserve quality of life," says Dr. Klotz, a professor in the Department of Surgery at the University of Toronto.