High-intensity focused ultrasound (HIFU) is a minimally invasive procedure that can be used to treat solid tumors—both benign and cancerous—in the prostate gland. For instance, HIFU may be an option for treating early-stage prostate cancer that has not spread beyond the prostate or a benign prostate tumor that is visible in imaging scans. An ideal candidate for HIFU has a small-to-medium-sized prostate gland with no major calcifications (dense tissue that sound waves cannot penetrate).
HIFU offers several benefits. The treatment does not involve surgical incisions, needles or radiation therapy, and because it is delivered with a high level of precision, it does not affect the surrounding healthy tissues. What's more, the risk of complications such as skin burns is low, and most patients recover from the procedure relatively quickly and can resume their regular activities within a few days.
How does HIFU work?
Many people are familiar with ultrasound imaging, which uses high-frequency sound waves to create detailed pictures of internal organs. High-intensity focused ultrasound also uses high-frequency sound waves, but instead of producing medical images, the sound waves are precisely focused on abnormal tissue, such as a tumor, to destroy it. Additionally, the sound waves used for HIFU are 10,000 times more powerful than the sound waves used for producing diagnostic images.
During HIFU, the highly targeted energy causes the temperature of the targeted tissue to rise, and the resulting heat destroys (ablates) the abnormal cells. The concept is similar to using a magnifying glass to concentrate the energy of the sun on a small spot to create heat and burn an object.
What does a HIFU procedure involve?
High-intensity focused ultrasound is typically delivered in a single outpatient session that lasts approximately two hours. The physician will evaluate imaging studies beforehand to determine the exact location of the abnormal tissue and plan the treatment. During the procedure, the patient will be positioned comfortably on an exam table. Once the patient is sedated, the physician will insert a thin ultrasound probe into the patient’s rectum to image the prostate and deliver the treatment.
Guided by real-time imaging, the physician will use the probe to deliver a test dose of high-frequency sound waves to the center of the targeted tissue, then adjust the strength of the ultrasound beams based on the depth of the tissue. Once the optimal intensity is set, the physician will deliver bursts of ultrasound waves to the targeted tissue while the rectum is actively cooled. Each burst will last only a few seconds and treat an area of tissue that is approximately the size of a grain of rice. Throughout the procedure, the surgeon will continually monitor real-time imaging as well as treatment parameters, such as temperature readings and calculated tissue changes, to evaluate the quality and success of the ablation.
When used for treating prostate cancer, the goal of high-intensity focused ultrasound is to treat only the area of the prostate with the tumor while leaving the rest of the gland and its surrounding structures intact and unaffected. This approach is widely used to successfully treat other types of cancer. In the case of multiple prostate tumors, the targeted tumor (index lesion) is the largest tumor with the highest grade. Many experts believe that the index lesion drives the behavior of the prostate cancer, and therefore treating it with HIFU can produce a good outcome.
Moffitt's approach to prostate cancer treatment
Moffitt Cancer Center is proud to offer the latest treatment options for prostate cancer, including high-intensity focused ultrasound and a robust portfolio of clinical trials, in a single location. If you were recently diagnosed with prostate cancer and would like to discuss your options with a specialist in our Urologic Oncology Program, please contact us at 1-888-663-3488 or complete our new patient registration form online to request an appointment. You can expect a rapid response from an expert within one day.