Focal Therapy with HIFU (High-Intensity Focused Ultrasound) - Information & Specialists

High-intensity focused ultrasound (HIFU) uses concentrated ultrasound waves. These waves converge at one or more points, where they generate a temperature of approximately 90 °C. The treated tissue heats up and the tumor cells die. The body then breaks them down.

Ultrasound devices contain a probe that emits the energy and a type of camera. This camera measures the affected area of the body and displays it as an image. This allows the doctor to direct the ultrasound precisely at the diseased area. Nearby areas (such as the rectum) are spared. The vascular-nerve bundles necessary for erections remain intact.

High-intensity focused ultrasound is primarily used to treat prostate cancer. The advantage of HIFU treatment is that it requires no incisions, implants, or radiation therapy. If the cancer recurs, another HIFU treatment is possible.

Focal therapy is suitable for the following types of prostate cancer:

• For the treatment of localized prostate cancer (Type 1/Type 2)
• For the treatment of recurrences (relapses)
• For treatment following brachytherapy or radiation therapy
• When surgery is not desired or not possible

Doctors now also use HIFU to treat breast cancer and benign tumors in the uterus (uterine fibroids). HIFU is also approved for the treatment of thyroid nodules. However, the HIFU procedure is not suitable for all types of thyroid tumors, but only for benign nodules.

HIFU treatment can gently destroy cancer cells in the prostate without damaging the surrounding tissue. @ wangmando / AdobeStock

During the procedure, the patient lies on a treatment table for approximately 1.5 to 2.5 hours. The treatment is usually performed under regional anesthesia. General anesthesia is also an option if the patient prefers it.

The doctor plans and controls the treatment process via a control panel. The computer-controlled system allows for precise guidance of the ultrasound probe, which minimizes the risk of side effects and complications. The doctor inserts the probe into the rectum and positions it directly next to the prostate. The probe then generates high-intensity focused ultrasound. If necessary, hundreds of ultrasound pulses can be triggered. The doctor continues the treatment until sufficient tumor tissue has been ablated.

The computer displays a three-dimensional image of the prostate on the screen. This allows the doctor to precisely define the tissue to be treated and deliver the ultrasound with millimeter-level accuracy. The ultrasound device is equipped with safety features that immediately interrupt the treatment if the patient moves.

There are several basic treatment strategies for HIFU therapy.

• Complete treatment (with or without nerve preservation):

If prostate cancer is detected on both sides, the doctor treats the entire gland. To do this, the doctor must remove prostate tissue using an electric loop inserted through the urethra. Depending on the location and aggressiveness of the tumor, nerve preservation may be possible.

• Hemiablation:

If the tumor is confined to one side, only half of the prostate is treated. In this case, it is not necessary to remove prostate tissue.

• Zonal treatment:

The treatment area includes the cancerous lesion and the immediately adjacent tissue.

• Focal therapy:

If there is a single, well-defined tumor, the doctor can treat it with ultrasound while maintaining a safe distance.

The higher the PSA level, the greater the likelihood of prostate cancer. @ angellodeco / AdobeStock

As a general rule, patients can walk again about five hours after treatment. The hospital stay following HIFU therapy usually lasts three to seven days.

Follow-up care after HIFU therapy takes place every three months. The PSA level serves as an indicator of treatment success. This value indicates how much prostate-specific antigen the prostate gland is producing. If the cancer has been destroyed, this value drops significantly. If the PSA level rises again, this is considered a relapse.

If the condition appears stable, follow-up appointments are initially extended to every six months and later to every twelve months.

The following side effects may occur immediately after HIFU treatment:

• Pain and mild burns
• Swelling: The surrounding tissue swells, so a urinary catheter may be necessary during the first few days.
• Blood in the urine: Often, the first few drops of urine are bloody during the first few weeks. In some cases, the urine contains small pieces of tissue. This is normal, as the dead tissue is being expelled in this way.
• Urethral obstruction: This occurs when too much tissue is shed at once. As a result, the initially strong urine stream weakens again. In this case, it is necessary to suction the tissue out through the urethra during a second inpatient procedure. Prostate shaving prior to HIFU treatment reduces the risk of this complication.
• Inflammation of the urethra, prostate, bladder, testicles, and epididymis: Although rare, this is possible. A prophylactic antibiotic prevents symptoms of infection such as frequent, urgent, and burning urination. This is not always successful. 
• Dribbling of urine when coughing, straining, or lifting heavy objects: This occurs because the external bladder sphincter is weakened. It affects approximately five percent of patients. This problem can usually be resolved through pelvic floor exercises.
• Erectile dysfunction: With a complete HIFU treatment (extending to the prostate capsule), there is a certain risk of damaging the neurovascular bundle. The result is erectile dysfunction. However, nearly 50% of patients retain their ability to achieve an erection completely.
• Fistula formation: In less than one percent of all patients, an abnormal connection forms between the intestine and the prostate.

Focal HIFU therapy is a minimally invasive treatment method for prostate cancer. It is particularly suitable for patients for whom surgery or radiation therapy is not an option. The procedure offers good chances of cure and improvement. However, no long-term data are available yet.

What is focal therapy for prostate cancer
? Focal therapy is a targeted treatment within the prostate in which only the detected tumor tissue is selectively destroyed, while healthy tissue is preserved.

Who is a candidate
for HIFU therapy? It is primarily suitable for men with locally confined prostate cancer, in whom the tumor is limited to the prostate and has not spread.

What Tests Are Required
Before Treatment? Before treatment, an MRI scan and targeted biopsies are required to precisely determine the location and extent of the tumor.

What does follow-up care involve after therapy
? Follow-up care includes regular monitoring of PSA levels as well as imaging tests to monitor the success of treatment and detect any changes at an early stage.