The management and site-specific prognostic factors of primary oral mucosal malignant melanoma.

Primary oral mucosal malignant melanoma (POMM) is uncommon. Its biological behavior is more aggressive than that of cutaneous malignant melanoma. Its site-specific prognostic factors and optimal management have not been determined yet. Retrospective POMM case analysis from peer-reviewed publications in the PubMed and Embase electronic database from January 1984 to December 2013, in which therapy and outcome data were available, was performed. A total of 151 primary cases were extracted from 39 peer-reviewed English literatures. The study population includes 63 males and 88 females with a medium age of 61 years. The treatment protocols include surgery alone (18%), radiotherapy alone (14%), surgery plus radiotherapy (14%), surgery plus chemotherapy (31%), as well as surgery plus chemoradiotherapy (15%) and chemoradiotherapy (8%). The male patients have a higher risk for metastasis than the female patients do (odds ratio [OR]; 3.41, P = 0.021). The POMM originating from specialized mucosa was associated with increased risk for tumor recurrence and mortality (OR, 4.03, P = 0.001; OR, 2.03, P = 0.031, respectively). The patients who had surgery-based multiple therapy have a significantly longer survival compared with those who had surgery alone and those who had no surgical treatment (P = 0.000). The age of 60 years or younger (hazard ratio [HR], 4.69; P = 0.000), nonsurgical treatment (HR, 12.838; P = 0.000), and surgery alone (HR, 1.517; P = 0.001) were independent adverse prognostic factors for overall survival. Taken together, the study results suggest that surgery-based multiple therapy is the most effective treatment protocol. The age of 60 years, nonsurgical treatment, and surgery alone were independent adverse prognostic factors for overall survival.