ESTRO 2025 - Abstract Book

S664

Clinical - CNS

ESTRO 2025

gastrointestinal cancer (15%) and malignant melanoma (14%). However, other neoplasms, including prostate carcinoma, sarcomas or renal cell carcinoma, were also represented. The median time interval between surgical intervention and the administration of radiotherapy was 27 days (range 9-109 days). The median OS was 31 months, with local control at 12 months of 92.5%. Symptomatic radionecrosis occurred in 3 patients (2.4%). Intracranial control at 12 months was 58.4%, while median iPFS was 17 months. Notably, 50% of local recurrences occurred in rectal and sigmoid cancers, which accounted for only 7% (11/163) of cases within the cohort. 15 patients subsequently underwent WBRT.

Conclusion: In summary, postoperative SFRT was very well tolerated and resulted in excellent local control rates. Further investigations will include recurrence pattern analyses and additional plan analyses to enhance the understanding of this radiation regimen. In addition, consideration should be given to dose adjustment for colorectal cancer.

Keywords: Brain metastasis, resection cavity, SFRT