Should radiotherapy be considered for the initial treatment of ovarian cancer brain metastases? Findings from a 12-year multicenter retrospective study.

e17541 Background: Ovarian cancer brain metastases (OCBM) are rare and have poor prognosis, with limited clinical guidelines. This study aims to identify prognostic factors and optimal treatment strategies for OCBM patients. Methods: We conducted a multicenter retrospective analysis of OCBM patients from 12 hospitals in China, spanning from May.1 2010 to May.31 2022. The primary endpoints were overall survival (OS) and brain metastasis-specific survival (BMSS). Kaplan-Meier and Cox regression analyses were used to assess treatment outcomes and identify risk prognostic factors. Results: A total of 129 OCBM patients were included. The median interval from ovarian cancer diagnosis to brain metastasis (BM) was 25.7 months (range: 0-102.9). Intracranial hypertension was the most common primary symptom reported in 64 (49.6%) patients, followed by paralysis in 23 (17.8%) patients. The cerebellum and brainstem were the most frequent sites of BM (36 patients, 27.9%), followed by the frontal lobe (27 patients, 20.9%). For BMSS-specific analysis, multiple BM lesions (HR 2.060, 95% CI: 1.308-3.244, p=0.002), intracranial hypertension (HR 1.765, 95% CI: 1.049-2.968, p=0.032), and relapse lines before BM diagnosis (HR 2.060, 95% CI: 1.308-3.244, p=0.002) as independent factors associated with poorer BMSS. Subgroup Kaplan-Meier analysis showed that patients with a single BM lesion had significantly better outcomes with stereotactic radiosurgery (SRS) compared to those with multiple lesions. Conclusions: This study identifies key prognostic factors for advanced OCBM patients, particularly intracranial hypertension, and the number of relapse-lines prior to BM diagnosis. Furthermore, it provides evidence that patients with a single BM lesion may benefit from SRS, whereas those with multiple lesions require more tailored treatment strategies. Univariate analysis of treatments for brain metastases. BM treatment OS BMSS Hazard ratio 95% CI P value Hazard ratio 95% CI P value Chemotherapy or support care Ref. Ref. WBRT ± Chemotherapy 0.78 0.412-1.477 0.446 0.652 0.334-1.274 0.652 Craniotomy ± Radiation/Chemotherapy 0.377 0.179-0.792 0.010 0.407 0.191-0.867 0.020 SRS ± Chemotherapy 0.270 0095-0.762 0.013 0.274 0.095-0.787 0.016 Abbreviations: BM: Brain metastasis; OS: Overall survival; BMSS: Brain metastases-specific survival; WBRT: Whole-brain radiotherapy; SRS: Stereotactic radiosurgery.