Primary oral mucosal melanoma: a series of 35 new cases from South America.

Oral mucosal melanoma is rare and reported to be more aggressive than its cutaneous counterpart. Due to the rarity of this entity, data on epidemiology, tumor behavior, treatment, follow-up, and survival of patients are mainly based on single case reports. The few existing series of patients show that oral mucosa melanoma has its peak between 41 and 60 years of age, and male to female ratio is 2:1. Preferred oral sites include hard palate and maxillary alveolar crests. Risk factors have not been clearly identified, and surgical treatment is still the treatment of choice for oral mucosal melanomas. The authors retrospectively studied 35 patients with primary melanoma of the oral cavity to report their clinical and pathological features, such as age, sex, site of the tumor, metastasis, treatment, response to therapy, and outcome. We found no significant sex predominance, and the mean age of the patients was 60.6 years, with a range from 9 to 91 years. The majority of the patients (71.42%) had palate commitment, and invasive histopathological aspect was observed in 80% of the specimens (grade 3). Long-distance metastasis was found in 60% of the cases. Fourteen patients were submitted to wide surgical resections, with local relapse being observed in 11 of them (78.5%). The authors suggest that improved outcome in oral malignant melanoma requires the development of new therapies and the prevention of distant metastasis.