ESTRO 2025 - Abstract Book

S695

Clinical - CNS

ESTRO 2025

Conclusion: This study evaluated the safety and potential benefits of adding SIB to HA-WBRT for patients with multiple brain metastases. At the final follow-up, the overall intracranial control rate was 77.8%. While the addition of SIB demonstrated a trend toward improved intracranial PFS, the difference was not statistically significant, likely due to the small sample size. Importantly, HA-SIB-WBRT appears to be safe and does not significantly increase toxicity. Further research with larger cohorts is needed to better assess its clinical utility.

Keywords: brain metastases, whole brain radiotherapy

References: 1. Brown PD, Gondi V, Pugh S, et al. Hippocampal Avoidance During Whole-Brain Radiotherapy Plus Memantine for Patients With Brain Metastases: Phase III Trial NRG Oncology CC001. J Clin Oncol . 2020;38(10):1019-1029. doi:10.1200/JCO.19.02767 2. Chia, B.S.H., Leong, J.Y., Ong, A.L.K. et al. Randomised prospective phase II trial in multiple brain metastases comparing outcomes between hippocampal avoidance whole brain radiotherapy with or without simultaneous integrated boost: HA-SIB-WBRT study protocol. BMC Cancer 20 , 1045 (2020). https://doi.org/10.1186/s12885-020 07565-yT

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Digital Poster Neurocognition and quality of life in patients receiving conformal cranial radiotherapy for brain metastases: A prospective study Kratika Bhatia 1 , Preetha Umesh 1 , Kundan Singh Chufal 1 , Irfan Ahmad 1 , Alexis Andrew Miller 2 , Balamrit Singh Sokhal 3 , Ram Bajpai 3 , Harsh Vyas 1 , Munish Gairola 1 1 Radiation Oncology, Rajiv Gandhi Cancer Institute & Research Centre, New Delhi, India. 2 Radiation Oncology, Illawara Cancer Care Centre, New South Wales, Australia. 3 School of Medicine, Keele University, Staffordshire, United Kingdom Purpose/Objective: The primary objectives of this prospective, single-institution study were to analyze the impact of conformal cranial radiotherapy techniques (stereotactic radiotherapy [SRT] and hippocampal avoidance whole-brain radiotherapy with simultaneous integrated boost [HA-WBRT+SIB]) on serially measured neurocognitive function (NCF) and quality of life (QoL) outcomes. The secondary objective was to compare intracranial progression-free survival (IC-PFS) between the two techniques. Material/Methods: This IRB-approved study enrolled 68 patients with brain metastases (BM) eligible for cranial radiotherapy. Patients received either SRT (27 Gy/3 fractions) or HA-WBRT+SIB (30 Gy/10 fractions to the whole brain, with a boost to 45 Gy/10 fractions for metastases ≥1 cc). NCF was assessed using the Mini-Mental State Examination (MMSE) and Hopkins Verbal Learning Test-Revised (HVLT-R), while QoL was evaluated using the EORTC BN-20 questionnaire. Assessments were conducted at baseline, 3 months, and 6 months post-radiotherapy. FSRT and HA-WBRT+SIB planning utlised T1-SPACE sequence, onto which all visible metastases were delineated. For FSRT, GTV was expanded by 3mm while for HA-WBRT+SIB they were expanded by 5mm. Hippocampal avoidance and constraints were as per RTOG 0933. Treatment planning and delivery was performed on Eclipse and TrueBeam, respectively. Linear mixed-effects modeling (LMM) was employed to analyze the longitudinal data, and Kaplan-Meier survival analysis evaluated IC-PFS.