Main clues in the pathologic diagnosis of melanoma: is molecular genetics helping?

[Malignant head and neck melanoma : Part 1: Diagnosis and histological particularities]

About 15% of all cutaneous melanomas develop in the head and neck region. Mucosal melanomas are rare and represent only 1% of all melanomas, however, most frequently, these are located in the nose, the paranasal sinuses and the oral cavity. Visual diagnosis and reflected-light microscopy are relevant for the evaluation of melanoma-suspect lesions. Histological investigation of resected tumors need special skills of the histopathologist and includes in case of high-risk tumors investigations of mutations in the tumor tissue concerning NRAS, BRAF and KIT. The risk of lymphatic or hematogeneous spread rises with increasing tumor thickness and the presence of further prognostic risk factors such as ulceration of the primary tumor or the presence of mitoses within the tumor.