Moderately hypofractionated external beam radiation therapy has become the standard of treatment for localised prostate cancer in most treatment centres [1,2]. Waikato Hospital also offers high-dose-rate brachytherapy monotherapy, which has been shown as a promising effective and safe treatment for localised prostate cancer [3]. The purpose of the audit was to assess the effectiveness and toxicity of high-dose-rate brachytherapy monotherapy (HDR-BT) and moderate hypofractionated external beam radiation therapy (EBRT) for low and intermediate risk prostate cancer.

Retrospective analysis of 131 patients with low to intermediate risk prostate cancer treated between 2015 and 2020 at Waikato Regional Cancer Centre. Low and intermediate risk prostate cancer was defined as per the National Comprehensive Cancer Network guidelines [4]. Acute toxicity was defined as within 9 months of radiation therapy. Gastrointestinal (GI) and genitourinary (GU) toxicity was assessed using the Common Terminology Criteria for Adverse Events (CTCAE) [5]. Biochemical failure was defined as per the Phoenix definition.

42 patients had HDR-BT (27Gy/2#) and 89 patients had hypofractionated EBRT (60Gy/20#). The median age was 67 (56-83) for the HDR-BT patients and 71 (47-83) for the EBRT patients. For the HDR-BT patients, 19% (8) had low and 81% (34) had intermediate risk disease respectively. For the EBRT patients, 6.7% (6) had low and 93.3% (83) had intermediate risk disease respectively. 19% (8) of HDR-BT patients had androgen deprivation therapy (ADT) whilst 29.2% (26) of EBRT patients had ADT. The mean prostate volumes were 41.7cc...

The findings of this study show that HDR-BT and moderate hypofractionated EBRT is a safe and effective way to treat low to intermediate risk prostate cancer patients. In our single centre experience, HDR-BT offers promising early efficacy and toxicity outcomes.

Catton C; Lukka H; Gu C; et al. Randomized Trial of a Hypofractionated Radiation Regimen for the Treatment of Localized Prostate Cancer. Journal of Clinical Oncology. 2017 June; 35(17). Dearnaley D; Syndikus I; Mossop H; et al. Conventional versus hypofractionated high-dose intensity-modulated radiotherapy for prostate cancer: 5-year outcomes of the randomised, non-inferiority, phase 3 CHHiP trial. The Lancet Oncology. 2016; 17(8): 1047-1060 Demanes JD, Ghilezan MI. High-dose-rate brachytherapy as monotherapy for prostate cancer. Brachytherapy. 2014; 13(6): 529-541 NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines®):...