ESTRO 2024 - Abstract Book

S427

Brachytherapy - Urology

ESTRO 2024

26. Henríquez I, Sancho G, Hervás A, Guix B, Pera J, Gutierrez C, et al. Salvage brachytherapy in prostate local recurrence after radiation therapy: predicting factors for control and toxicity. Radiat Oncol Lond Engl. 2014 Apr 30;9:102. 27. Dinis Fernandes C, Ghobadi G, van der Poel HG, de Jong J, Heijmink SWTPJ, Schoots I, et al. Quantitative 3-T multi-parametric MRI and step-section pathology of recurrent prostate cancer patients after radiation therapy. Eur Radiol. 2019;29(8):4160 – 8. 28. Pfister D, Haidl F, Nestler T, Verburg F, Schmidt M, Wittersheim M, et al. 68Ga-PSMA-PET/CT helps to select patients for salvage radical prostatectomy with local recurrence after primary radiotherapy for prostate cancer. BJU Int. 2020;126(6):679 – 83. 29. Corkum MT, Buyyounouski MK, Chang AJ, Chung HT, Chung P, Cox BW, et al. Salvage prostate brachytherapy in radiorecurrent prostate cancer: An international Delphi consensus study. Radiother Oncol J Eur Soc Ther Radiol Oncol. 2023 Jul;184:109672. 30. Goupy F, Supiot S, Pasquier D, Latorzeff I, Schick U, Monpetit E, et al. Intensity-modulated radiotherapy for prostate cancer with seminal vesicle involvement (T3b): A multicentric retrospective analysis. Zhang Q, editor. PLOS ONE. 2019 Jan 25;14(1):e0210514.

2370

Digital Poster

Is there a link between the dose to prostate sectors in LDR brachytherapy and biochemical outcomes?

Orla A Houlihan 1,2 , Sergio Esteve 3 , Owen McLaughlin 1,3 , Geraldine Workman 3 , Monica Byrne 3 , Eoin Napier 4 , Kevin M Prise 1 , Alan R Hounsell 3 , Darren M Mitchell 2 , Suneil Jain 1,2 1 Queen’s University Belfast, Patrick G. Johnston Centre for Cancer Research, Belfast, United Kingdom. 2 Northern Ireland Cancer Centre, Belfast City Hospital, Clinical Oncology, Belfast, United Kingdom. 3 Northern Ireland Cancer Centre, Belfast City Hospital, Radiotherapy Medical Physics, Belfast, United Kingdom. 4 Northern Ireland Cancer Centre, Belfast City Hospital, Radiology, Belfast, United Kingdom

Purpose/Objective:

Biochemical outcomes following low dose rate (LDR) prostate brachytherapy include biochemical recurrence (defined as per the Phoenix criteria as a rise in PSA of 2 ng/mL greater than the nadir PSA) and PSA bounce (defined as a PSA increase of ≥ 0.2 ng/ml followed by spontaneous return to pre -bounce level or lower) [1]. Biochemical recurrence is an indication that prostate cancer has recurred [2]. PSA bounce has been shown in a recent systematic review and meta-analysis to be associated with lower rates of biochemical recurrence and, therefore, more favourable outcomes among patients who experience a PSA bounce compared to those who do not experience a PSA bounce [3]. Spatial dose mapping by dividing the prostate gland into reproducible sectors is an established, recognised method of analysis of the dose distribution delivered during LDR prostate brachytherapy