High-Intensity Focused Ultrasound (HIFU) is a non-invasive treatment option for men diagnosed with localized prostate cancer. This technology uses focused energy to destroy cancerous tissue without surgical incisions. HIFU offers a balance between effective cancer control and a reduced risk of side effects compared to traditional whole-gland therapies. This review examines the procedure, its outcomes, and how it compares to other established treatment methods.
The HIFU Procedure: Mechanism and Candidacy
HIFU relies on thermal ablation, the destruction of tissue using heat. A specialized probe is temporarily placed in the rectum, directing high-frequency ultrasound waves through the rectal wall into the prostate gland. These sound waves are precisely focused to converge at a specific point, similar to how a magnifying glass focuses sunlight. At this focal point, the energy rapidly heats the targeted tissue to temperatures exceeding 70°C (158°F), causing immediate cell death.
HIFU is primarily considered for men with clinically localized, low-to-intermediate risk prostate cancer. Patient selection is based on factors such as PSA levels, Gleason score, and the extent of cancer spread. Many centers utilize HIFU as a focal therapy, treating only the area containing the known tumor rather than the entire prostate gland. This focal approach is suitable for men with cancer confined to one side or a specific region, though whole-gland treatment remains an option.
Reported Cancer Control and Efficacy
Oncological success is measured by HIFU’s ability to eradicate the tumor and maintain a disease-free state. Whole-gland HIFU has demonstrated encouraging long-term results, with specific survival rates reported between 92% and 99% in studies up to 10 years. For the focal approach, studies show the cancer-specific survival rate is effectively 100% at five years post-treatment. Focal HIFU successfully prevents the return of clinically significant cancer in the treated area in approximately 95% of cases.
Monitoring for recurrence involves regular checks of Prostate-Specific Antigen (PSA) levels, which should decrease significantly and then stabilize following treatment. A continuous rise in PSA can signal a possible recurrence, prompting further investigation. Follow-up protocols frequently include magnetic resonance imaging (MRI) and a control biopsy, often performed around six months after the procedure, to confirm cancer elimination.
Some patients may experience biochemical failure (a rise in PSA) or a local recurrence. The retreatment-free survival rate—the percentage of patients who do not require a second intervention—is estimated to be around 71% at three years in some cohorts. The likelihood of recurrence or the need for retreatment is higher for men who present with unfavorable intermediate-risk or high-risk disease. If cancer does return, HIFU does not preclude the use of other treatments, such as repeat HIFU, surgery, or radiation therapy.
Quality of Life: Functional Outcomes and Recovery
HIFU reduces the impact on urinary and sexual function compared to radical treatments. The preservation of urinary continence is high following focal HIFU, with studies reporting that 97% to 100% of men remain pad-free. The overall rate of urinary incontinence requiring any pads can be as low as 2% in focal therapy patients. This high preservation rate is due to the targeted nature of the treatment, which spares the urinary sphincter and surrounding tissues.
Erectile function preservation is also improved with focal HIFU compared to whole-gland ablation or surgery, with preservation rates often exceeding 78% in sexually active men. Since the treatment is precisely focused to avoid the delicate nerve bundles alongside the prostate, the risk of severe erectile dysfunction is minimized.
The non-invasive nature of HIFU contributes to a relatively fast recovery period. The procedure is typically performed on an outpatient basis, allowing patients to return home the same day. Due to temporary swelling from thermal ablation, a urinary catheter is usually required for several days (often four to seven days). Most men resume normal daily activities within two weeks, without the restrictions associated with major surgery.
HIFU vs. Established Prostate Cancer Treatments
HIFU is often contrasted with radical prostatectomy (surgical removal) and external beam radiation therapy (EBRT). HIFU is minimally invasive, resulting in lower rates of long-term urinary incontinence and erectile dysfunction than surgery or radiation. A prospective study comparing HIFU with radical prostatectomy found that functional outcomes, including continence and sexual function, were significantly better in the HIFU group.
While radical prostatectomy has historically been the standard, matched-pair studies show HIFU can achieve similar nine-year overall survival, cancer-specific survival, and metastasis-free survival rates. However, the need for a secondary treatment, such as salvage radiation, may be higher after HIFU compared to radical prostatectomy in some long-term data. A limitation of HIFU is the relative lack of comparative data spanning more than ten years, which is available for surgery and radiation.
HIFU occupies a specific place in the treatment landscape, often reserved for men with localized disease who prioritize functional outcome preservation. The decision between HIFU, surgery, or radiation depends heavily on the cancer’s characteristics, the patient’s health status, and personal priorities regarding side effects. Consulting with a specialist who offers all treatment modalities is recommended for a comprehensive understanding of the options.