Using high energy ultrasound beams to terminate prostate cancer tumors may be as effective as surgery or radiotherapy, but with fewer side effects.
A new study, conducted by six hospitals across the UK, tracked 625 men with prostate cancer who received a type of treatment called high-intensity focused ultrasound (HIFU).
The research, published in the journal European Urology, is the largest ever study to date of HIFU treatment used to target prostate tumors. The treatment is similar to a 'lumpectomy' for other cancers -- where doctors remove only tumor cells, leaving as much healthy tissue as possible.
The conclusions, from a number of institutions including Imperial College London and University College London, found that after five years the cancer survival rate from HIFU was 100%. Approximately 1 in 10 men needed additional treatment. The cancer survival rate from surgery and radiotherapy is also 100% at five years.
The research also highlighted the risk of side effects of HIFU, such as urinary incontinence and erectile dysfunction, were lower than other treatment options, at 2 percent and 15 percent respectively.
Professor Hashim Ahmed, lead author from the Department of Surgery and Cancer at Imperial, said: "Although prostate cancer survival rates are now very good, the side effects of surgery or radiotherapy can be life-changing. Some patients are left requiring several incontinence pads every day, or with severe erectile dysfunction."
He added: "We need to now focus on improving the quality of life for these men following treatment. This latest trial of focal HIFU -- which is the largest and longest study of the treatment to date -- suggests we may be able to tackle the cancer with fewer side effects."
Treatments include surgery to remove the gland, or radiotherapy, which uses radiation to the entire prostate. However, these treatments can cause collateral damage to surrounding sensitive tissues like nerves, muscles, urine passage, bladder, and rectum.
Surgery and radiotherapy to the entire prostate are effective treatments but can lead to long-term risk of urinary problems, like incontinence, of between 5-30 percent. They also carry a risk of erectile dysfunction of between 30-60 percent. Radiotherapy can also cause rectal problems like bleeding, diarrhea, and discomfort in 5 percent of patients.
HIFU is a newer treatment, performed under general anesthetic, which delivers beams of high energy ultrasound directly into the prostate gland, via a probe inserted up the back passage. This allows a surgeon to accurately target tumor cells within the gland to millimeter precision, with less risk of damage to surrounding tissues. There are no needles or cuts to the skin.
In the new HIFU study, carried out on men with an average age of 65 and whose cancer hadn't spread, the risk of urine incontinence (defined as requiring pad use) at five years after the treatment was 2 percent, and the risk of erectile dysfunction 15 percent. The team says the results include patients with medium to high-risk cancer.
The scientists also tracked the number of patients who needed additional treatment following HIFU, (such as surgery or radiotherapy), to treat any cancer cells that had returned. They found 10 percent of patients needed further treatment by five years, which is comparable to the number of patients needing further treatment after surgery or radiotherapy (5-15 percent).
Further follow-up trials are required to track progress of the patients after ten years, as well as trials that directly compare HIFU with surgery and radiotherapy.
The full study at Imperial College London can be found here.