ESTRO 2024 - Abstract Book

S431

Brachytherapy - Urology

ESTRO 2024

1. Burchardt W, Skowronek J. Time to PSA rise differentiates the PSA bounce after HDR and LDR brachytherapy of prostate cancer. J Contemp Brachytherapy. 2018;10(1):1-9.

2. Simon NI, Parker C, Hope TA, Paller CJ. Best approaches and updates for prostate cancer biochemical recurrence. Am Soc Clin Oncol Educ Book. 2022;42:1-8.

3. Urabe F, Kimura S, Tashiro K, Kido M, Sasaki H, Aoki M, et al. Prognostic value of PSA bounce in prostate cancer following definitive radiation therapy: a systematic review and meta-analysis. Prostate Cancer Prostatic Dis. 2021;24(4):976-85. 4. Nath R, Bice WS, Butler WM, Chen Z, Meigooni AS, Narayana V, et al. AAPM recommendations on dose prescription and reporting methods for permanent interstitial brachytherapy for prostate cancer: report of Task Group 137. Med Phys. 2009;36(11):5310-22.

2605

Poster Discussion

HDR brachytherapy boost plus EBRT in unfavorable prostate cancer: results in more then 700 patients

Ivone Ribeiro 1 , Juan Ignacio Rodríguez-Melcón 1 , Víctor Ferrándiz 1 , Mario Federico 1 , Juan Zafra-Martin 2,3 , Alba Domínguez Domínguez 1 , Daniel Aguiar Santana 1 , Juan Luís Pérez-Molina 4 , Eduardo Rodríguez-Serafin 4 , Ana Tornero 4 , Victoria Morato Garcia 4 , Beatriz Pinar 1 , Marta Lloret 1 1 Gran Canaria Dr. Negrín University Hospital, Radiation Oncology Department, Las Palmas de Gran Canaria, Spain. 2 Virgen de la Victoria University Hospital, Radiation Oncology Department, Málaga, Spain. 3 Institute of Biomedical Research in Málaga (IBIMA), Group of Translacional Research in Cancer Immunotherapy (CIMO2), Málaga, Spain. 4 Gran Canaria Dr. Negrín University Hospital, Medical Physics Department, Las Palmas de Gran Canaria, Spain

Purpose/Objective:

To report early and late toxicity and clinical results of external beam radiotherapy (EBRT) followed by a single dose of high-dose-rate (HDR) brachytherapy (BT) in a prospective cohort of intermediate and high-risk prostate cancer (pCa) patients.

Material/Methods:

720 patients with a median age at diagnosis of 68 years (47-81) were treated between December 2014 and March 2023. Tumor characteristics are described in table 1. Androgen-deprivation therapy was administered to 97.5% of patients. Median baseline IPSS was 4 (IPSS ≥15 2.92%). Multiparametric -MRI at diagnosis was obtained in 65.3% of patients (86.4% since 2018). EBRT was administered in 13 fractions of 2.8 Gy each (total dose of 36.4 Gy) to the prostate and seminal vesicles in intermediate-risk patients, and 23 fractions of 2 Gy each to the whole pelvis in high risk patients. 98.9% of patients were treated with volumetric arc radiotherapy. Image guidance was performed with cone-beam CT in 93.8%. HDR brachytherapy was administered with a single fraction of 15 Gy as a boost to prostate