Comparative mortality following intracranial hemorrhage in patients with brain metastases from melanoma vs renal cell carcinoma: A propensity score–matched analysis.

Abstract

e14027 Background: Melanoma and renal cell carcinoma (RCC) frequently metastasize to the brain and carry high hemorrhagic risk, yet comparative outcomes following intracranial hemorrhage (ICH) remain poorly characterized. Methods: Using TriNetX (111 healthcare organizations), we identified adults with nontraumatic ICH (2016-2025) and brain metastases within one year prior. Patients were stratified by primary malignancy (melanoma vs RCC) after excluding concurrent diagnoses, vascular malformations, and coagulopathies. Propensity score matching (1:1) balanced cohorts on demographics, comorbidities, and laboratory values. Primary analysis examined 1-day to 1-year outcomes; landmark analyses at 90 and 14 days assessed survivors. Cox and logistic regression evaluated outcomes. Results: After matching, 561 patients per cohort were analyzed. Melanoma patients had significantly higher one-year mortality (52.9% vs 37.9%; HR 1.69, 95% CI 1.42-2.02, p<0.001; number needed to harm 7, 95% CI 5-11). This difference persisted among 90-day survivors (HR 1.60, 95% CI 1.17-2.20, p=0.003) and in the 90-day subgroup (HR 1.75, 95% CI 1.41-2.16, p<0.001), with consistent findings at the 14-day landmark. No significant differences were observed in thromboembolic events, neurosurgical interventions, or other secondary outcomes; however, statistical power was limited for these endpoints. Conclusions: Patients with ICH and brain metastases from melanoma experience significantly higher mortality compared to RCC, persisting beyond the acute period, suggesting tumor biology rather than ICH severity drives this disparity. Cox proportional hazards regression analysis (melanoma vs RCC). Outcome Primary Index–1yr Landmark 90d–1yr Subgroup Index–90d Landmark 14d–90d Mortality 1.69 (1.42–2.02)* 1.60 (1.17–2.20)* 1.75 (1.41–2.16)* 1.67 (1.30–2.15)* ED Visits 0.96 (0.60–1.53) 1.00 (0.47–2.12) 0.94 (0.52–1.71) 0.63 (0.31–1.30) Inpatient Visits 1.25 (0.63–2.48) NR NR NR Hospice Enrollment 1.10 (0.56–2.16) NR 1.34 (0.63–2.85) NR Ischemic Stroke 1.26 (0.69–2.29) NR 1.05 (0.54–2.06) 1.19 (0.51–2.80) Acute VTE 1.14 (0.71–1.83) NR 1.45 (0.82–2.56) 1.61 (0.83–3.13) STEMI/NSTEMI 1.01 (0.51–2.03) NR 1.20 (0.53–2.71) NR Blood Transfusions 0.83 (0.47–1.46) NR 0.94 (0.47–1.86) NR Craniotomy/EVD/Shunt 1.09 (0.57–2.08) NR 1.15 (0.60–2.21) NR Mechanical Ventilation 1.29 (0.77–2.15) NR 1.18 (0.67–2.09) 1.08 (0.45–2.59) Values represent Hazard Ratio (95% CI). Reference group: RCC. *p<0.05. NR=not reported due to insufficient events (<10 in one group). Proportional hazards assumption satisfied for all mortality analyses (Schoenfeld test p>0.35). Secondary outcomes were underpowered; null findings should be interpreted cautiously.