Prognostic factors in mucoepidermoid carcinoma of the salivary glands

BACKGROUND: Mucoepidermoid carcinoma (MEC) is the most common malignancy of the major salivary glands. Prior reports noted histological grade and tumor stage as consistently important prognostic factors. This study reviewed the experience of patients with MEC at the University of Texas MD Anderson Cancer Center to determine the impact of clinical and pathologic findings on disease outcomes. METHODS: A retrospective clinical review was performed of patients with salivary gland MEC treated at a tertiary cancer center from 1990 to 2007. RESULTS: A total of 125 patients were included. The 5-year overall survival and disease-free survival of all patients were 79.3% and 76.5%, respectively. Patients with low- and intermediate-grade disease had significantly better overall survival and disease-free survival than patients with high-grade disease, but no difference in survival rates was found between low- and intermediate-grade disease. Pathologic results of positive lymph nodes, extracapsular lymph node spread, and perineural invasion were all found to be poor prognostic indicators. On multivariate analysis, advanced disease stage and perineural invasion were found to be the most significant prognostic factors. CONCLUSIONS: Patients with either low- or intermediate-grade tumors uniformly have favorable local control and survival. High histological grade, advanced stage, perineural invasion, positive surgical margins, and submandibular location all portend for poor outcomes in MEC. Further advances in therapy are needed to improve outcomes for high-grade and advanced-stage disease. Cancer 2012. (c) 2011 American Cancer Society.