BXTAccelyon has responded to an article on the Daily Mail that claims that a ten-minute shot of High Dose-Rate (HDR) radiation treatment is a “safe and effective” choice for low-risk prostate cancer patients.
The article reports that a three year study of prostate cancer patients from the Christie Hospital in Manchester and Mount Vernon in London claims that a one-hit treatment of HDR brachytherapy cuts the risk of side-effects and reduces the toxic impact of radiotherapy treatment when compared to external-beam radiation therapy (EBRT), which it terms ‘lower-strength’ radiotherapy.
However, the article both confuses HDR brachytherapy with radiotherapy and fails to refer to alternative findings from clinical data that offer a contrary view on this treatment option, which should be appropriately termed as ‘single fraction HDR’.
Rather than radiotherapy, which is an external treatment, brachytherapy is an internal treatment delivering radiation to the tumour site. Brachytherapy can be either a permanent implant that delivers low-dose radiation (LDR-B) or a temporary implant that delivers a higher dose over multiple sessions (HDR-B). HDR-B has been trialled as a single session, or fraction, treatment, with clinical data still being assessed.
In contrast to the Christie Hospital & Mount Vernon study, research presented at the largest UK & NI conference of Brachytherapy experts, that convened last month offered a contrary view. Clinical trial data presented by Gerard Morton, Affiliate Scientist, Sunnybrook Health Sciences Centre, Toronto, included research from an independent Spanish study* which indicated that single fraction HDR-B monotherapy produced unacceptable levels of bDFS (Biochemical Disease-Free Survival), at 66% after 5 years compared to significantly higher levels with other established surgical and radiotherapy treatments. bDFS is one of the key measures used to determine the long-term efficacy of radiotherapy treatments.
Morton also presented research which highlighted that this form of HDR treatment is associated with more late urinary symptoms when compared to alternative treatment options, and whilst Toxicity from single fraction is slightly less in the first 12 months, it does get worse beyond 3 years. Moreover, data from Sunnybrook’s own randomised trial indicated that single fraction HDR-B monotherapy (19g) drives the lowest level response to PSA, compared to a 27gr-2 fraction treatment – meaning that the cancer is not responding as well.
This is borne out by the American Brachytherapy Society, whose consensus guidelines for HDR-B (published in 2012) concluded that different HDR prescription doses all had similar outcomes in terms of toxicity and disease control and therefore ‘no particular dose fractionation can be recommended’.
There are many treatment options available to prostate cancer patients – from radical prostatectomy and EBRT, to HDR-B and LDR-B, as well as brachytherapy boosts in combination with EBRT, which allow a highly conformal dose of radiation to be delivered to the prostate in a safe, efficient manner and deliver highly effective, clinically proven results.
Prostate cancer patients – especially those at early stages of diagnosis – are in a vulnerable position. The right treatment for any patient is a highly personalised decision and needs to take into consideration both the cancer diagnosis itself as well as a patient’s lifestyle choices. It is therefore the duty of medical professionals, and those publishing ‘guidance’ in any form, to provide fully considered and informed facts.
*Study = “High-dose rate interstitial brachy as monotherapy in one fraction” Prada, Cardenal, Blanco et al