Oral malignant melanoma of the oral cavity is rare. Although the Asian population has a relatively high incidence of oral malignant melanoma in contrast to Caucasians, the clinical information in Korean has been rarely known. In addition, the clinical and histological classification of oral malignant melanoma has not been established up to now. So we investigated 26 cases of oral malignant melanomas on the basis of clinicopathological and immunohistochemical findings and reclassified the clinical and histological type. The results of this study are as followed. Oral malignant melanomas occurred at any age from 28 years to 73 years and their mean age was 58.6 years. Of 26 cases, 14 occurred in male and 12 in female. Oral malignant melanomas occurred almost in palate and/or maxillary gingiva (25 cases; 96.2%). Only one case occurred in mandibular gigiva. Oral malignant melanomas were clinically divided into macular(9 cases) and nodular type(17 cases), showing that the nodular type occurred more frequently. Oral malignant melanomas were histologically divided into in situ spreading(5 cases), invasive(13 cases), and combined type(8 cases), showing that the invasive type occurred most frequently. All cases showed positivity for S-100 and 15 cases(57.7%) for HMB-45 in immunohistochemical analysis. It was thought these results could provide basic data for the research on oral malignant melanoma in Korean and additional prospective and retrospective studies would be needed in order to find the relations with the prognosis of the patients

This r esearch was designed to find the specific and economic methods of diagnosis about malignant melanoma For this study, we selected a typical case that was ambiguous in diagnosis between malignant melanoma and simple mela notic pigmentation, Tissue sections was st ained by H&E method, and immunohistochemical analyses was performed about 8-100 protein and MART-1 molecule, This research showed that MART-l had a more specificity for melanocytes than 8-100 protein , Patterns of MART-1 molecule distribution was more helpful in estimation of malignancies than 8-100 protein distribution patterns, On the basis of diagnostic usefulness and economical aspects, 8-100 protein and MART-1 molecule showed synergis tic and complementary relationship in confirming of tumor origin and they would be much useful for accurate diagnosis of malignant melanoma