ESTRO 2025 - Abstract Book

S1889

Clinical - Urology

ESTRO 2025

protocol showed consistent bladder volumes and may improve patient convenience during prostate SBRT. Late adverse effects are awaited.

Keywords: Prostate SBRT, Empty bladder

References: [1]

V. Murthy et al. , “OC -0924 Prostate RT In high risk or N+ Moderate vs Extreme hypofractionation (PRIME): An Interim analysis,” Radiotherapy and Oncology , vol. 182, pp. S770 – S771, May 2023, doi: 10.1016/S0167-8140(23)08750 9.

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Digital Poster advancing nephroblastoma treatment: insights from the role of radiotherapy Bilal El alaoui, Fatima zohra Zaanoun, Fatima zahra Abdelli, Samia Khalfi, Kawtar Soussy, Wissal Hassani, Fatima zahraa Farhane, Zenab Alami, Touria Bouhafa radiotherapy, chu hassan II, fes, Morocco

Purpose/Objective: To evaluate the role of radiotherapy in the treatment of nephroblastoma.

Material/Methods: We conducted a descriptive retrospective study including 31 children treated for nephroblastoma at the radiotherapy department of Hassan II University Hospital, Fès, between January 2014 and December 2023. Results: The average age of patients was 3.7 years (range: 9 months - 12 years), with a female predominance (71%). Consanguineous marriage was noted in 25.8% of cases. None of the patients had a predisposition syndrome or family history of nephroblastoma. The average delay from symptom onset to diagnosis was 48 days (range: 7 days to 7 months), with abdominal distension as the main symptom (61.3%). The most frequent histological type was mixed (29%), followed by blastemal-predominant (25.8%), with high risk in 54.8% of cases and intermediate risk in 45.2%. Most patients were diagnosed at stage III (74.19%). In terms of treatment, 96.8% of patients received neoadjuvant chemotherapy according to the GFA Nephro-2005 protocol, except for one patient who underwent immediate surgery. All patients subsequently underwent total extended ureteronephrectomy via a transperitoneal approach, followed by adjuvant chemotherapy. Each patient received three-dimensional conformal radiotherapy with a curative intent, administered on average 45 days post surgery (range: 26 to 90 days). Sedation was required for 51.6% of patients. Irradiation sites included the flank (45.2%), the whole abdomen (35.5%), lung and flank (16.1%), and lung and lumbar spine (3.2%), with an average total dose of 17.5 Gy (range: 10.5 to 30 Gy), spread over 13 days (range: 8 to 30 days). Outcomes showed complete remission in 17 patients (54.8%), partial remission in 4 patients (12.9%), and recurrence in 7 patients (22.6%) with a total of 10 deaths (32.3%). Conclusion: Nephroblastoma is a highly radiosensitive tumor, and the use of radiotherapy in specific contexts, such as advanced stages and recurrences, proves beneficial in improving local control. Radiotherapy thus serves as a cornerstone of multimodal treatment for this tumor, enhancing survival prospects and quality of life.

Keywords: nephroblastoma, treatment, radiotherapy