title: HLA-DR antigen expression in primary melanomas of the skin.
abstract: Ninety-three primary malignant melanomas of the skin were typed immunohistologically for the expression of HLA-DR on tumor cells. HLA-DR-positive stroma cells were HLA-DR-negative or only locally positive in most cases. In 36 (39%) of the lesions more than 10% of the tumor cells were stained by two monoclonal antibodies against the nonpolymorphic portion of HLA-DR. HLA-DR-positive tumor cells were often accumulated at the advancing front of the melanoma. The occurrence of HLA-DR-positive tumor cells was related to tumor thickness and level of invasion. Substantial numbers of HLA-DR-positive tumor cells were found in half of the tumors thicker than 1.5 mm and in only 18% of flatter lesions. The highest percentage of HLA-DR-positive tumors was found in the group of melanomas invading the reticular dermis (level IV). The majority of tumors (18/24) that had metastasized within an observation period of 0-32 months were HLA-DR-positive. Regarding the mononuclear cell infiltrate, no correlation between the degree of overall infiltrate and the expression of HLA-DR by the tumor cells was found. The infiltrate within the tumor, however, was more often marked in HLA-DR-positive than in HLA-DR-negative melanomas.
mesh_terms: D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm / Q000276:immunology; D006684:HLA-DR Antigens; D000949:Histocompatibility Antigens Class II / Q000276:immunology*; D006801:Humans; D007124:Immunoenzyme Techniques; D008545:Melanoma / Q000276:immunology*; D012878:Skin Neoplasms / Q000276:immunology*
chemical_list: D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm; D006684:HLA-DR Antigens; D000949:Histocompatibility Antigens Class II