Light Therapy And Prostate Cancer

Light therapy can effectively help out men who have low to medium risk of developing prostate cancer. The evidence to support this theory was attained when phase III clinical trials were conducted.

A study conducted on over 400 men with localized traces of prostate cancer showed the effectiveness of a treatment approach called vascular-targeted photodynamic therapy (VTP). VTP solely focuses on killing the targeted cancerous cells in prostate cancer patients, while unleashing no harm to the surrounding healthy tissues. The study also revealed that using VTP as a treatment option can eliminate the need of radical therapy which employs irradiation or removal of the prostate entirely.

The lead investigator, consultant urologist and dean of Medical Sciences at University College London, UK, Prof. Mark Emberton along with his colleagues reported the findings of their study to The Lancet Oncology.

Protocols For Prostate Cancer

In US, next to skin cancer the incidence of prostate cancer is second highest in men. For men with localized prostate cancer, the first protocol usually offered is active surveillance, in which by using PSA (prostate specific antigen) and DRE (digital rectal exam), the cancer is thoroughly screened. At times biopsies may as well be done but the treatment is only provided in case the cancer worsens. However if the cancer does not aggravate, the treatment approaches are limited to:

• Prostatectomy: in this procedure, the prostate is surgically removed along with nearby normal tissues.
• Radiation therapy

These treatment options can also bring along undesired adverse effects like urinary incontinence, bowel related issues, persistent erectile dysfunction.

But the findings of Prof Emberton’s study suggested that VTP can minimize the need of all such procedures if it is given in the early stages of the illness.

VTP was introduced by Weizmann Institute of Science, Israel in association with STEBA Biotech, a biotechnology based company.

VTP treatment involves injecting of WST11 into the bloodstream, a drug with light sensitive properties which is derived from the ocean bacteria. Once the drug is activated using a laser, the drug emits free radicals that effectively destroys the cancerous cells present in the prostate.

In Prof. Emberton’s phase III trial study, 413 men having early diagnosis of localized cancer were selected from 10 European countries and were offered active surveillance protocol. 206 of these patients randomly received VTP treatment whereas the rest of the patients were categorized as the control group (and received active surveillance). The follow up of these patients lasted for a period of 2 years in which the PSA testing was done regularly and erectile and urinary functions were assessed at every 3 months. Prostate biopsies were also conducted by the end of each year.

The findings revealed of the study were as following:

• 49% of the VTP treated patients entered complete remission in contrast to the 13.5% patients who were given active surveillance.
• Only 6% of VTP treated men needed radical therapy in comparison to the 30% of patients who weren’t offered VTP.
• VTP slowed the progress of prostate cancer and doubled the progression time from 14 months all the way to 28 months.
• No side effects were reported to be linked with VTP treatment after a 2 years study.

Therefore, it is safe to say that VTP can significantly help men with early diagnosis of localized prostate cancer.

References:

• Kim, K., Watson, P. A., Jebiwott, S., Somma, A. J., La Rosa, S. P., Mehta, D., ... & Coleman, J. (2016). Androgen deprivation therapy potentiates the efficacy of vascular targeted photodynamic therapy of prostate cancer xenografts.
• Azzouzi, A. R., Barret, E., Moore, C. M., Villers, A., Allen, C., Scherz, A., ... & Emberton, M. (2013). TOOKAD® Soluble vascular‐targeted photodynamic (VTP) therapy: determination of optimal treatment conditions and assessment of effects in patients with localised prostate cancer. BJU international, 112(6), 766-774.