A new experimental treatment for localized prostate cancer that uses high intensity focused ultrasound (HIFU) promises to be more effective and have fewer side effects than conventional treatments, according to a new study published early online in The Lancet Oncology on Tuesday.
HIFU, which involves removing small lumps of cancerous prostate tissue, is being investigated as an alternative to conventional treatments such as radical whole-gland removal (radical prostatectomy) in men with localized prostate cancer. In this respect it is similar to the option of a “lumpectomy” as an alternative to a full mastectomy in breast cancer.
The treatment focuses soundwaves to millimetre accuracy, causing targeted tissue to heat up to around 80 to 90 degrees Celsius, which kills cells instantaneously.
The first author of the study is Hashim Uddin Ahmed, a Medical Research Council Clinical Research Fellow in the Division of Surgery and Interventional Science at University College London (UCL), who is conducting a series of world-first trials into HIFU as an alternative treatment for prostate cancer.
Prostate cancer is the most common cancer affecting men in the UK where 250,000 are currently living with the disease, and 37,000 cases are diagnosed every year.
Conventional treatments such as surgery and radiotherapy can cause many distressing side effects that affect everyday life, work and relationships.
This is because they treat the whole prostate and risk damaging the nerves that supply the penis, muscles that control urine flow, and the lining of the rectum. Damage to these nerves leads to incontinence and difficulty having erections.
Thus there is a need for new kinds of treatment that safely remove cancerous tissue without damaging surrounding nerves.
For this latest phase 1 study, between June 2007 and June 2010, Ahmed and colleagues recruited 42 men, of age 45 to 80 years, with low to high risk localized prostate cancer who had not yet undergone any cancer treatment.
The men received HIFU to all known cancer lesions (some had only one, others had several lesions).
One man died of causes unrelated to the cancer three months after treatment, so only 41 were included in the analyses.
12 months after the start of HIFU treatment (some men had it more than once), none of the 41 men had incontinence, only one in 10 suffered from poor erections, and the majority (95%) were free of cancer.
Ahmed and colleagues conclude:
“Focal therapy of individual prostate cancer lesions, whether multifocal or unifocal, leads to a low rate of genitourinary side-effects and an encouraging rate of early absence of clinically significant prostate cancer.”
Ahmed told the press the results are “very encouraging” and he and his colleagues are “optimistic” that in the not too distant future, men diagnosed with localized prostate cancer will be able to undergo HIFU as a day case surgical procedure, which can safely be repeated once or twice, with few side effects.
“That could mean a significant improvement in their quality of life,” Ahmed said in a report by the Press Association.
Ahmed said the findings furnish the necessary “proof of concept” that gives the go-ahead to much larger trials to investigate the effectiveness of HIFU as a standard treatment for men with localized prostate cancer.
Funds from the Medical Research Council (UK), Pelican Cancer Foundation, and St Peters Trust helped pay for the study.
Written by Catharine Paddock PhD