Impact of Infratentorial Location on Survival After Surgical Resection of Brain Metastases: A Multicenter Retrospective Study

Abstract Purpose Infratentorial brain metastases (BMs) pose distinct clinical challenges, but their prognostic relevance remains unclear. This study evaluated the impact of infratentorial location on survival after surgical resection. Methods A total of 1,434 patients who underwent surgery for BMs between 2016 and 2023 at three German neurosurgical centers were screened. After applying exclusion criteria, 921 patients were included in the final analysis. Survival outcomes were compared between patients with supratentorial and infratentorial metastases, and prognostic factors for poor outcome were analyzed. Results The median age was 63 years (IQR 55—71), and 50.3% were male. The most common primary tumors were NSCLC (51.6%) followed by breast cancer (14.9%) and melanoma (13.5%). Infratentorial metastases were present in 29.5% of patients and were associated with significantly higher rates of hydrocephalus (19.9% vs. 4.2%, OR 5.7, p < 0.001) and shorter postoperative survival (7.6 vs. 9.0 months, OR 1.22, p = 0.014). Multivariate analysis confirmed infratentorial location as an independent predictor for poor survival (OR 0.65, p = 0.015), along with Graded Prognostic Assessment score (OR 1.74, p = 0.01), gastric carcinoma histology (OR 0.32, p = 0.036), and lack of adjuvant therapy (OR 0.98, p = 0.001). Conclusion Infratentorial BMs are linked to worse outcome after surgery and should be considered as an independent adverse prognostic factor. Incorporating anatomical location into prognostic models may improve risk stratification and guide clinical decision-making.