The popular actor Ben Stiller, who had prostate cancer, had his prostate removed. (Photo : Getty Images)
A new non-surgical treatment for low-risk prostate cancer has been found to effectively kill cancer cells while preserving healthy tissue.
The new treatment is called "Vascular-Targeted Photodynamic therapy" (VTP).
It involves injecting a light-sensitive drug into the bloodstream and then activating it with a laser to destroy tumor tissue in the prostate. The research found that around half (49%) of patients treated with VTP went into complete remission compared with 13.5% in the control group.
Published in The Lancet Oncology, the study reports a new phase III clinical trial in 413 patients led by University College London (UCL). The trial was funded by STEBA Biotech, which holds the commercial license for the treatment
"These results are excellent news for men with early localized prostate cancer, offering a treatment that can kill cancer without removing or destroying the prostate," said lead investigator Professor Mark Emberton, Dean of UCL Medical Sciences and Consultant Urologist at UCLH.
"This is truly a huge leap forward for prostate cancer treatment, which has previously lagged decades behind other solid cancers such as breast cancer. In 1975 almost everyone with breast cancer was given a radical mastectomy, but since then treatments have steady improved and we now rarely need to remove the whole breast.
"In prostate cancer we are still commonly removing or irradiating the whole prostate, so the success of this new tissue-preserving treatment is welcome news indeed."
Today, men with low-risk prostate cancer are put under "active surveillance" where the disease is monitored and only treated when it becomes more severe.
Radical therapy, which involves surgically removing or irradiating the whole prostate, has significant long-term side effects, and is only used to treat high-risk cancers.
Radical therapy causes lifelong erectile problems and around one in five patients also suffer from incontinence.
By contrast, VTP only caused short-term urinary and erectile problems, which resolved within three months. No significant side-effects remained after two years.
In the trial, only 6% of patients treated with VTP needed radical therapy compared with 30% of patients in the control arm who were under active surveillance.
The chances of cancer progressing to a more dangerous stage were three times lower for patients on VTP, and the treatment doubled the average time to progression from 14 months to 28 months.
The trial involved 47 treatment sites from ten different European countries, most of which were performing VTP for the first time.
"The fact that the treatment was performed so successfully by non-specialist centers in various health systems is really remarkable," said Professor Emberton, who is supported by the National Institute for Health Research University College London Hospitals Biomedical Research Center.
"New procedures are generally associated with a learning curve, but the lack of complications in the trial suggests that the treatment protocol is safe, efficient and relatively easy to scale up. We would also expect the treatment to be far more precise if we repeated it today, as technology has come a long way since the study began in 2011.
"We can now pinpoint prostate cancers using MRI scans and targeted biopsies, allowing a much more targeted approach to diagnosis and treatment. This means we could accurately identify men who would benefit from VTP and deliver treatment more precisely to the tumor.
"With such an approach we should be able to achieve a significantly higher remission rate than in the trial and send nearly all low-risk localized prostate cancers into remission.
"We also hope that VTP will be effective against other types of cancer -- the treatment was developed for prostate cancer because of the urgent need for new therapies, but it should be translatable to other solid cancers including breast and liver cancer."
The VTP treatment is currently being reviewed by the European Medicines Agency (EMA), so it is likely to be a number of years before it can be offered to patients more widely.
