Is Ultrasound Effective Against Prostate Cancer?
CancerWise - November 2008
By Dawn Dorsey
A new clinical trial is testing the effectiveness of high-intensity focused ultrasound (HIFU) as a treatment option for patients newly diagnosed with early prostate cancer.
M. D. Anderson is participating in the national Phase II/III trial of HIFU, an experimental, non-invasive procedure that heats and destroys the tumor but does not harm surrounding tissue.
“Having a choice of treatments is a good thing, and HIFU is another possible approach for men who have small tumors and want to be proactive,” says John Ward, M.D., assistant professor in M. D. Anderson’s Department of Urology and the lead investigator at the cancer center. “This therapy has been used in Europe to treat 17,000 men with various stages of prostate cancer, and from that experience it appears to be a promising balance between effective cancer treatment and few long-term side effects.”
Significance of study
Researchers hope HIFU will provide some men with a treatment that doesn’t require an incision and poses less chance of damage to healthy tissue around the tumor.
“We’re closely watching the outcome of this national clinical trial,” Ward says. “HIFU could lead the way toward a new path of non-invasive procedures in which the tumors are destroyed, but the delicate tissues and structures are not affected.”
Although HIFU is not yet approved by the U.S. Food and Drug Administration for use in this country, it is widely practiced in Europe, Latin America, China, Japan and Canada. Ward says many men from the United States travel to other countries for the procedure.
Goal of the study
“Physicians around the world have safely and effectively used HIFU for many years,” Ward says. “However, we need this domestic trial to demonstrate HIFU’s place among many other effective and proven treatment options.”
The study will compare HIFU, which uses heat, to cryosurgery, which uses freezing, to determine if they are equally effective in killing prostate tumors.
Pioneered at M. D. Anderson, cryosurgery is a standard of care surgical treatment for localized prostate cancer. Other options, becoming more common but not studied in the trial, include watchful waiting (observing small, inactive prostate tumors), external radiation and brachytherapy (implantation of radioactive “seeds”).
“The next therapeutic extension of heating or cooling prostate tissue to effect prostate cancer cure will be to use the thermally ablative technologies to treat only the cancerous portion of the prostate with therapy involving either the heating or cooling afforded by HIFU and cryotherapy,” Ward says. “In fact we are already conducting a study of focal cryotherapy alongside the HIFU trial for men who may not qualify to undergo HIFU.”
The HIFU procedure, which uses robotic technology, takes two to three hours to complete.
A dual-action ultrasound wand is inserted into the rectum next to the prostate. First, the ultrasound waves locate the prostate and divide it into precise treatment zones.
Then waves are focused on the treatment area. They heat tissue to between 80 degrees and 100 degrees Celsius, resulting in its destruction.
The HIFU procedure:
- Kills cancerous cells with high-energy sound waves
- Is similar to lithotripsy, a treatment for kidney stones
- Requires a general or a spinal anesthetic
- Is usually performed on an outpatient basis
- Requires catheterization (a minimum of two weeks)
Possible side effects
Some patients may have:
- Temporary slight swelling in the groin area
- Urine retention
To be eligible for this study, men must:
- Be 60 years old or older
- Have a low-grade, localized prostate cancer
- Have a prostate-specific antigen (PSA) less than 10
Some patients eligible for this trial also may be eligible for other non-invasive treatment options, such as watchful waiting, cryotherapy or radiation therapy.
For more information, call askMDAnderson at 1-877-632-6789.