Craniofacial Resection for Malignant Melanoma of the Skull Base

Abstract

OBJECTIVE: To report postoperative mortality, complications, and outcomes in a subset of patients with the histologic diagnosis of malignant melanoma extracted from an existing database of a large cohort of patients accumulated from multiple institutions. DESIGN: Retrospective outcome analysis. SETTING: Seventeen international tertiary referral centers performing craniofacial surgery for malignant skull base tumors. PATIENTS: A total of 53 patients were identified from a database of 1307 patients who had craniofacial resection for malignant tumors at 17 institutions. The median age was 63 years. Of the 53 patients, 25 (47%) had had prior single modality or combined treatment, which included surgery in 22 (42%), radiation in 11 (21%), and chemotherapy in 2 (4%). The margins of resection were close or microscopically positive in 7 (13%). Adjuvant radiotherapy was given in 22 (42%), chemotherapy in 3 (6%), and vaccine or interferon therapy in 2 (4%). Complications were classified into overall, local, central nervous system, systemic, and orbital. Overall survival (OS), disease-specific survival (DSS), and recurrence-free survival (RFS) were determined using the Kaplan-Meier method. Predictors of outcome were identified by multivariate analysis. RESULTS: Postoperative mortality occurred in 3 patients (6%) and postoperative complications were reported in 14 patients (26%). Local wound complications occurred in 6 patients (11%), central nervous system in 7 (13%), systemic in 3 (6%), and orbital in 1 (2%). With a median follow-up of 10 months (range, 1-159 months), the 3-year OS, DSS, and RFS rates were 28.2%, 29.7%, and 25.5%, respectively. The extent of orbital involvement and adjuvant postoperative radiation therapy (PORT) were independent predictors of DSS and OS on multivariate analysis, whereas only PORT was an independent predictor of RFS. Patients treated with PORT had significantly better 3-year OS (39% vs 18%; relative risk, 2.9; P = .007), DSS (41% vs 19%; relative risk, 3.0; P = .007), and RFS (39% vs 15%; relative risk, 4.2; P = .001). CONCLUSIONS: Craniofacial resection in patients with malignant melanoma of the skull base has mortality (6%) and complication rates (26%) comparable to other malignant tumors of the skull base. However, malignant melanoma is associated with a much poorer OS, DSS, and RFS. Adjuvant PORT correlated with improved 3-year OS, DSS, and RFS on multivariate analysis. These factors must be taken into account when considering craniofacial resection in a patient with malignant melanoma invading the skull base.