Middle Meningeal Artery Embolization for Chronic Subdural Hematoma in Cancer Patients: A Propensity-Matched Cohort Study of 90-Day Outcomes

BACKGROUND: Cancer patients with chronic subdural hematoma (cSDH) face higher recurrence and surgical risk. Middle meningeal artery embolization (MMAE) has emerged as a minimally invasive treatment for cSDH, but evidence is limited as cancer patients are mostly excluded from trials. METHODS: Using the TriNetX US Collaborative Network, we identified adults with nontraumatic cSDH and a neoplasm diagnosed within one year before the index event. We performed four 1:1 propensity-score-matched comparisons: MMAE versus medical management and surgery plus MMAE versus surgery alone (both within cancer patients), and cancer versus no cancer within the medically managed and surgical cohorts. Outcomes were 90-day all-cause mortality and rescue surgery, assessed with Kaplan–Meier estimates and Cox proportional-hazards models. RESULTS: Among cancer patients, MMAE versus medical management (694 matched pairs) was associated with lower 90-day mortality (15.3% vs 20.9%; HR 0.69, 95% CI 0.53–0.89; p=0.004), with no significant difference in rescue surgery (6.8% vs 4.5%; p=0.10). Adding MMAE to surgery (355 pairs) was associated with fewer rescue operations (8.8% vs 13.7%; HR 0.63, 95% CI 0.40–0.99; p=0.04) and numerically lower mortality (10.4% vs 13.4%; p=0.19). Cancer was associated with higher mortality among medically managed patients (18.5% vs 15.8%; p<0.001) and higher rescue surgery among surgical patients (14.9% vs 11.4%; p<0.001). CONCLUSION: MMAE was associated with a lower need for repeat surgical intervention in cancer patients with cSDH without raising mortality or complications. It is a safe, minimally invasive alternative to repeated surgical drainage for this high-risk group.