Abstracts Archive

UK & Ireland Prostate Brachytherapy Conference 2019

Abstract number 3

Outcomes from intermediate risk, Gleason 7, localised prostate cancer treated with low-dose rate brachytherapy 

Maher R, Gatfield E, Lees K, Beesley S 
Kent Oncology Centre, Maidstone Hospital, Kent 

Introduction: Low-dose rate (LDR) brachytherapy is a treatment option for men with low and intermediate risk, localised prostate cancer. This audit assessed the outcomes for patients with intermediate risk disease comparing initial Gleason pattern 3+4=7 and 4+3=7 disease, treated with iodine-125 brachytherapy, at a single UK centre. 

Methods: Retrospective analysis of 294 patients who received LDR brachytherapy at Maidstone Hospital, between 2008 and 2016 inclusive. 262 patients had initial Gleason pattern 3+4=7 and 32 patients had 4+3=7 disease. Primary end-points included overall survival (OS), progression-free survival (PFS) and biochemical PFS. 

Results: Median follow up was 47.6 months (4.9-117.1 months). Mean presenting PSA was 7.6ng/ml (2.4-19.8ng/ml). 5 year OS was 94.7% (95% CI 92.1-97.3%). No patients died due to their prostate cancer. 17 patients developed radiologically or biopsy confirmed local (12) or metastatic (5) recurrence, with a crude failure rate of 5.78% (17/294). 5 year PFS was 93.6% overall (95% CI 90.8-96.4), Gleason pattern 3+4=7 disease 94.0% (95% CI 91.1-96.9) and 4+3=7 disease 90.0% (95% CI 79.6-100.4). Fisher’s exact test (Gleason 7) = 1, p>0.05. There were an additional eight patients with biochemical failure. 5 year biochemical PFS was 90.6% overall (95% CI 87.3-93.9), Gleason pattern 3+4=7 disease 91.4% (95% CI 88.0-94.8) and 4+3=7 disease 83.9% (95% CI 71.2-96.6). Fisher’s exact test (Gleason 7) = 0.7453, p>0.05. 

Conclusion: LDR brachytherapy is an extremely good treatment option for patients with localised, intermediate risk prostate cancer. The small relative numbers of Gleason 4+3=7 disease in this study is acknowledged, however these results have shown that, despite a suggestion of a trend to a worse 5 year biochemical PFS, there is no statistical difference in overall survival between the two groups. We feel that LDR brachytherapy can be considered an appropriate treatment option for both low and high intermediate risk disease, in selected cases.