S158
Brachytherapy - Urology
ESTRO 2026
Keywords: prostate cancer, salvage therapy, brachytherapy
strictures. Severe rectal toxicity was rare (5.2%). A trend toward increased ≥ G3 toxicity was observed with larger prostate volumes (>45 mL; p=0.104). No dosimetric parameters were significantly associated with high-grade toxicity. Median PSA declined from 6.6 ng/mL at diagnosis to 1.34 at 3 months, 0.57 at 12 months, and 0.07 at 5 years; median PSA nadir was 0.01 ng/mL. At a median follow-up of 135 months, 91.3% of patients remained free from biochemical recurrence, with overall survival of 86.7% and cancer- specific survival of 99.4%. Patients with recurrence had significantly lower total implanted activity (29.7 vs. 34.6 mCi, p=0.027) and higher PSA values during follow-up (p<0.01). PSA ≥ 1 ng/mL at 6 months strongly predicted biochemical failure, confirmed by multivariate analysis across all timepoints (p<0.01). Conclusion: LDR prostate brachytherapy provides durable biochemical control with low severe toxicity . PSA ≥ 1 ng/mL at 6 months strongly predicts recurrence, highlighting early PSA as a robust biomarker for long- term disease control. Keywords: LDR, prostate cancer References: Grimm PD, Blasko JC, Sylvester JE, Meier RM, Cavanagh W. 10-year biochemical (prostate-specific antigen) control of prostate cancer with (125)I brachytherapy. Int J Radiat Oncol Biol Phys. 2001;51(1):31-40.Morris WJ, Keyes M, Spadinger I, et al. Population-based 10- year oncologic outcomes after low-dose-rate brachytherapy for low-risk and intermediate-risk prostate cancer. Cancer. 2013;119(8):1537-46.Keyes M, et al. Late Urinary Side Effects 10 Years After Low- Dose-Rate Brachytherapy. Red Journal. 2014.Fels F, et al. Permanent interstitial low-dose-rate brachytherapy for prostate cancer: institutional experience with implementation and predictive factors for outcome and side effects. (J Radiotherapy in Practice, 2023) Oncologic outcome and toxicity after focal salvage HDR brachytherapy in locally recurrent prostate cancer after radiotherapy Marnix J.A. Rasing 1,2 , Max Peters 1,2 , Carmen P. Liskamp 3 , Wietse S.C. Eppinga 1 , Sandrine M.G. van de Pol 1 , Juus L. Noteboom 1 , Jan J.W. Lagendijk 1 , Jochem R.N. van der Voort van Zyp 1 1 Radiation Oncology, University Medical Center Utrecht, Utrecht, Netherlands. 2 Radiation Oncology, Radiotherapiegroep, Deventer, Netherlands. 3 Radiation Oncology, Haaglanden Medical Center, Den Haag, Netherlands Poster Discussion 1099
Digital Poster 1046
Over a decade of durable tumor control and low toxicity with LDR prostate brachytherapy – a single-center experience María Cerrolaza 1 , Agustina Mendez 1 , Cristina Garcia 1 , Claudia Colom 1 , Victoria Navarro 2 , Maria del Mar Puertas 1 , Ana Galan 1 , Claudia Laborda 1 , Andrea Ochoa 1 , Javier Diez 3 , Pablo Alares 4 , Reyes Ibañez 1 1 Radiation Oncology, Miguel Servet University Hospital, Zaragoza, Spain. 2 Radiation Oncology, Lozano Blesa University Clinical Hospital, Zaragoza, Spain. 3 Physics, Miguel Servet University Hospital, Zaragoza, Spain. 4 External Consultant, in collaboration with the Department of Radiation Oncology, Miguel Servet University Hospital, Zaragoza, Spain Purpose/Objective: Low-dose-rate (LDR) prostate brachytherapy is an established treatment for localized prostate cancer, offering efficacy with favorable toxicity and quality-of- life profiles. Most data are from cohorts with limited follow-up. We present a long-term evaluation of patients treated at our center to assess the durability and safety of this approach. Material/Methods: We retrospectively analyzed 173 patients with low- or favorable intermediate-risk prostate cancer treated with LDR brachytherapy. Baseline patient and tumor characteristics, implant and dosimetric parameters were recorded. Follow-up every 6 months included PSA measurements and quality-of-life questionnaires, with toxicities graded by CTCAE v5.0. Outcomes included biochemical recurrence, overall and cancer- specific survival, statistical analysis was conducted, considering p < 0.05 as significant. Results: : Median follow-up was 135 months (11.25 years; IQR 36 months). Patients had a median age of 67 years and median PSA of 6.6 ng/mL at diagnosis, with 91.3% presenting ISUP grade 1 disease. Mean prostate volume was 38.2 mL, with 19.7 needles and 65.7 seeds implanted. Median total activity was 33.3 mCi, with optimal dosimetry (V100 97.5%, D90 176 Gy). Urinary function showed a transient deterioration post- treatment: median IPSS increased from 6 pre- brachytherapy to 15–16 at 1–3 months, returning to 8– 9 within 6–12 months. Erectile function (IIEF-6) decreased from 12 at baseline to 1–2 at 3 months, with partial recovery (6–10) at 12–36 months. Severe urinary toxicity ( ≥ G3) occurred in 26 patients (15%). Acute events included urinary retention and prostatitis, while late events were mainly urethral
Made with FlippingBook - Share PDF online