Melanoma of the oral cavity. Review of the literature.

Melanoma is a very aggressive tumour derived from malignant transformation of melanic cells of the basal layer of cutaneous and mucosal epithelia. Primary melanoma of the oral cavity is the most malignant tumour among head and neck tumours. Inside the oral cavity, 80% are located in the maxilla, preferentially in the palatal mucosa. Although its etiology is unknown, occasionally it forms over a preexisting melanosis of prolonged evolution. In the vast majority of cases it is asymptomatic during years and it is usually detected as a pigmented mass which is sometimes painful. Doctors who treat problems of the oral cavity must be aware of the necessity for early diagnosis of melanoma, performing biopsies of any pigmented lesion. Once it becomes clinically evident, its tendency is to grow toward adjacent structures and to form metastases in cervical lymphatic nodes, turning the tumour into a systemic disease. Prognosis of melanoma in the oral cavity is very poor. The only curative treatment is ablative surgery. Other therapeutic modalities such as: radiotherapy, chemotherapy or immunotherapy have supposed little contribution to improve survival.