New photodynamic laser therapy for low-risk prostate cancer can effectively kill cancer cells when preserving healthy tissue, according to a new study. Scientists are using prostate cancer treatment into the 21st century with a new method that uses lasers and ocean bacteria to target the disease rather than surgery.
A study published in The Lancet Oncology describes a process known as vascular-targeted photodynamic therapy, also known as VTP, which involves injecting a light-sensitive drug into the patient’s blood and then using a laser to activate the drug, which then kills cancerous tissue.
The researchers first collected data from more than 400 patients with “low-risk, localized prostate cancer,” which was previously untreated at a few dozen European medical centers between 2011 and 2013. Half of the men received light therapy, while the other half were simply monitored. When the researchers followed up with the patients about two years after their treatment, about 28 percent of those who were treated with the light therapy had seen a progression in their disease, as compared to more than half of the group of men who were not treated in that way.
The scientists saw other differences in outcomes too: According to the study, almost half of the VTP group were in remission two years after their treatment, compared to only 14 percent of the non-treated men in the other group.
In addition to its effectiveness, the new treatment can kill early-stage cancer without damaging or removing the prostate and healthy tissue, unlike the surgery and irradiation used to treat higher-risk cancers. Those two treatments may also cause long-term erectile issues and incontinence.
The study notes, however, that the common side effect in the VTP group was difficulty urinating, but it occurred in just 15 of the more than 200 men who were treated, and it “resolved” within a couple of months.
“This is truly a huge leap forward for prostate cancer treatment,” lead investigator Mark Emberton, of the University College London, said in a statement from that institution. “In 1975, almost everyone with breast cancer was given a radical mastectomy, but since then treatments have steadily 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.”
Gerald, a man aged in his 60s from Surrey, was one of the first patients to be treated with VTP under the care of Emberton. He said: “The treatment changed my life. I’m now cancer-free with no side-effects and don’t have to worry about needing surgery in the future. I feel so lucky to be in this position. I’ve met other men who had surgery – they had to stay in the hospital for days, whereas I could go home the next day, and one suffered from terrible incontinence, which he found very distressing. I had some minor side-effects for a few weeks after the operation, but I’m back to normal now.”
Each year, more than 46,000 men in the UK are diagnosed with prostate cancer, and 11,000 die from the disease.
The standard of care for men with low-risk prostate cancer is active surveillance, which involves monitoring of prostate-specific antigen (PSA) levels, digital rectal exams, or prostate biopsies. As radical therapy, which involves surgically removing or irradiating the whole prostate, it has significant long-term side effects, including erectile dysfunction and incontinence, it is only used to treat high-risk cancers.