Survival and prognostic factors in mucosal melanomas of the oral cavity: A meta-analysis

The development of early metastases due to the high vascularization and lymphatic drainage of the oral cavity, followed by delayed diagnosis, results in a worse prognosis of oral melanomas. The present study aimed to determine the survival of oral melanoma in different periods and analyze its prognostic factors.

A search for studies on survival and prognostic factors of oral melanoma was performed in the following databases: PubMed (MEDLINE, Cochrane Library), Web of Science (WoS), and Scopus. The estimation of the pooled proportion was carried out with the generic inverse variance method, using the standard error (SE) of the proportion. For dichotomous outcomes, the estimates of the effects of the intervention were expressed as odds ratios (ORs) using the Mantel-Haenszel (M-H) method, all with 95% confidence intervals.

Thirty-eight studies that considered 3767 oral melanoma patients were included in this meta-analysis. Overall survival (OS) decreased from 58% at two years to 42% at three years and 29% at five years. Regarding prognostic factors, non-ulcerated oral melanomas with a high degree of pigmentation showed the best survival at 5 years. In contrast, oral tumor location and gender did not significantly affect oral melanoma survival.

Oral melanoma has a low survival rate, with ulcerated and poorly pigmented tumors having the worst prognosis.