Surgical series of metastatic cerebral melanoma: Clinical association of resection, BRAF-mutation status, and survival

Abstract

BackgroundMajor advances in the systemic treatment of metastatic cerebral melanoma have improved patient survival. The clinical relationship between gross total resection (GTR), BRAF-mutation status, and its effects on survival in the era of targeted/immunotherapy warrants further characterization. MethodWe retrospectively reviewed survival after craniotomy for melanoma metastases in patients who also received targeted/immunotherapy and cavity radiation at four neurosurgical hospitals in Queensland, Australia from 2012 to 2019. Results152 craniotomies were performed in 138 patients (98 male, 40 female), 42% were BRAF-mutant with differences in median age for BRAF-mutant vs BRAF-wildtype (52 vs 64 years; p = 0.001), and GTR rates for BRAF-mutant vs BRAF-wildtype (85% vs 73%; p = 0.03). Median survival difference between BRAF-mutant vs BRAF-wildtype was 15.4 vs 11.9 months (p = 0.11). The longest median survival occurred in BRAF-mutant with GTR while the shortest occurred in BRAF-wildtype with STR (23 vs 4.5 months; p = 0.001). At three years, the proportion alive for GTR and BRAF-mutant vs GTR and BRAF-wildtype (47.9% vs 41.6%) was higher than STR and BRAF-mutant vs STR and BRAF-wildtype (15% vs 28.4%; p = 0.03). ConclusionBRAF-mutant patients with cerebral metastases were younger, and more likely to have a higher GTR rate with greater survival than BRAF-wildtype if GTR is achieved. Gross total resection in both groups appears to be associated with survival even in the current era of more effective systemic therapies. Subtotal resection has particularly poor survival, especially for BRAF-mutant patients.