Ongoing data show high-intensity focused ultrasound's promise in low-risk prostate cancer

Key Points

Vail, CO-High-intensity focused ultrasound (HIFU), while still years away from clinical use in the United States, shows promise as a first-line treatment for low-risk prostate cancer, a leading researcher of the therapy reported at the International Prostate Cancer Update here.

"This is the best minimally invasive treatment I have ever seen for low-grade, low-stage prostate cancer," said Cary N. Robertson, MD, associate professor urology at Duke University Medical Center, Durham, NC. "It offers good local control, which satisfies the goal of any definitive treatment, with minimal side effects compared to other options currently available. It's also a procedure that is relatively easy to learn."

Another European study included 227 men with T1-2 localized prostate cancer, PSA ≤15.0 ng/mL, and Gleason score ≤7, prostate volume ≤40 cc, and no previous radical treatment for prostate cancer who underwent HIFU (Eur Urol 2007; 51:381-7). At mean post-treatment follow-up of 12 to 121 months, 86% of the men had negative control biopsies and a median nadir PSA of 0.10 ng/mL. The actuarial 5-year disease-free survival rate was 66%. Treatment-related adverse events included incontinence (1%-6%), recto-urethral fistula (0%-0.5%), and erectile dysfunction (10%-50%).

The HIFU procedure uses focused ultrasound to ablate tissue inside the prostate. While the patient is under local or general anesthesia, a lubricated probe is inserted into the rectum. An initial ultrasound of the prostate is performed to create a three-dimensional image that can be visualized on a computer screen. After the surgeon defines the target volume, the computer is programmed and the robotic probe carries out the treatment plan automatically.

During treatment, tissue effects are visible during each focal burn, Dr. Robertson explained. Rectal cooling is provided by a cooling solution around the probe and adjacent to the rectal wall, while computer software monitors the rectal wall thickness to ensure safety. The entire treatment lasts approximately 2 hours, depending on the volume of the prostate. After treatment, urinary retention is almost universally experienced, and a catheter is placed for 7 to 14 days. Pain can be managed with nonsteroidal anti-inflammatory drugs.

Dr. Robertson said that about 15% of patients with localized prostate cancer are good candidates for HIFU treatment.

"The ideal patient is a man with a small gland-less than 25-cc volume prostate-who has low-volume disease," he said.