What is the Success Rate of Low-Dose Rate Brachytherapy?
A positive diagnosis of prostate cancer can seem devastating to men and their families. But it doesn’t have to be that way. If caught early, prostate cancer has a good survival rate – around 475,000 men in the UK are either living with, or after, prostate cancer.
There are a number of treatment options available to men, from no intervention (active surveillance) to full removal of the prostate (radical prostatectomy). There are also a range of less invasive treatments men may be offered, or may wish to seek out.
In choosing your treatment option, there are two main things to consider. The first is the success rate of the treatment given, in terms of both recurrence-free or overall survival (OS) – i.e. the cancer doesn’t return – and in terms of biochemical failure (PSA levels that don’t increase again over time). The second is the potential side-effects or implications of the treatment on your lifestyle.
Here, we take a look at some of the considerations and the success rate of low-dose-rate brachytherapy (LDR-B). You can read more about LDR-B treatment itself here.
Rich Evidence Base
LDR-B has been an established treatment for prostate cancer for over two decades and has a rich and growing evidence base of long-term outcomes.
A 2012 comparative effectiveness study by the Prostate Cancer Study Group – which evaluated over 50,000 patients with low, intermediate and high-risk prostate cancer treated with all available primary options[1],[2] – found that 95% of patients that have LDR-B treatment are disease-free at 15 years.
In addition, the 2018 ASCENDE-RT study[3] – the first randomised controlled trial to compare the outcomes of two types of treatment in intermediate and high-risk prostate cancer patients – found LDR-B showed better recurrence-free survival (RFS) rates. The study showed that at 9 years, RFS in the patients treated with LDR-B boost in combination with EBRT (external beam radiotherapy) was 83% compared to 62% in those treated with dose-escalated EBRT. The study also revealed that patients receiving a DE-EBRT boost were twice as likely to have biochemical failure (increased PSA levels) compared to LDR-B boost.
Finally, a recent study on prostate cancer overall survival (OS) outcomes – conducted by the Yale School of Medicine and published in the European Association of Urology in November 20176 – reports that LDR-B boost is associated with better overall survival for men with unfavourable (higher risk) prostate cancer, when compared to external radiotherapy. The findings match results from other large randomised trials that indicate the efficacy of LDR-B boost and suggest that improvements in biochemical control may mean better overall survival with additional follow-up.
LDR-B Eligibility
Low-dose rate brachytherapy can be a suitable treatment for any patient, irrespective of age and the risk-grade of their cancer diagnosis. Despite active surveillance being the default position for low-risk cancer, as many as 70% of younger patients treated for prostate cancer receive radical prostatectomy. The quality of life and patient experience implications are significant.
A recent study published in the New England Journal of Medicine[4] revealed that surgery to remove the prostate has the greatest impact on sexual function and urinary continence compared to other treatments. Our own research reveals that younger patients are typically offered only one or two of the five current treatment options for prostate cancer, with only 11% receiving advice on three or more available options. At 61%, surgery is the most widely recommended.
Where it’s appropriate, the patient experience benefits make LDR-B an attractive option for younger patients. Studies show that the risk of incontinence after brachytherapy is far lower than in surgery and radiation[5]. It’s also associated with shorter recovery times and reduced overall treatment time – making it less disruptive for younger patients.
In addition, both the ASCENDE-RT and Yale studies highlighted above, independently show that LDR-B is a highly viable option for not just low-risk prostate cancer, but also intermediate- and high-risk.
What Happens in The Case Cancer Returns?
On the rare occasions that recurrence happens – and we should not forget that 95% of patients opting for LDR-B are proven to be disease-free at 15 years – surgery is a distinct possibility. There is a widespread belief that patients who opt for LDR-B are ineligible for so-called ‘salvage treatment’ should their cancer reappear.
This misconception that LDR-B patients are not eligible for salvage treatment is a factor in the limited uptake of brachytherapy. Many centres believe that if more patients realised that they could have salvage treatment should their LDR-B fail, many more would opt for it as a first choice.
Conclusion
As outlined, the majority of men diagnosed with prostate cancer will only get advice on a couple of treatment options, with the majority being recommended radical surgery – despite its known side effects. In contrast, LDR-B is a long-standing, proven treatment that is a highly viable – yet often discounted – option for many men.
It is, therefore, important to consider the potential side effects and outcomes of any cancer treatment, and it is always advisable to speak with your consultant or specialist nurse to get a full picture of what is available to you. We encourage all men and their families to discuss all their treatment options before deciding, however difficult it may seem.
[1] Grimm PD, Billiet I, Bostwick D et al. Comparative analysis of prostate specific antigen free survival outcomes for patients with low, intermediate and high risk prostate cancer treatment by radical therapy. Results from the Prostate Cancer Results Study Group. BJU Int 2012; 109(Suppl 1): 22–29
[2] Chao, MWT, Grimm P et al. Brachytherapy: state-of-the-art radiotherapy in prostate cancer. BJU Int 2015; 116, Supplement 3, 80–88
[3] Morris WJ, Tyldesley S, Pai HH, et al. ASCENDE-RT*: a multicenter, randomized trial of dose-escalated external beam radiation thera- py (EBRT-B) versus low-dose-rate brachytherapy (LDR-B) for men with unfavorable-risk localized prostate cancer. J Clin Oncol 2015;33(Suppl 7):3.
[4] Donovan JL, et al. Patient-Reported Outcomes after Monitoring, Surgery, or Radiotherapy for Prostate Cancer, N Engl J Med 2016;375:1425-37. DOI:10.1056/NEJMoa1606221
[5] Buron C, Le Vu B, Cosset JM et al. Brachytherapy versus prostatectomy in localized prostate cancer: results of a French multicenter prospective medico‐economic study. Int J Radiat Oncol Biol Phys 2007; 67: 812–22