Infiltration of primary and metastatic melanomas with macrophages of the 25F9-positive phenotype.
In order to gain insight into the role of macrophages in human melanoma, we studied fresh-frozen material from 15 dysplastic nevi, 199 primary melanomas, 107 melanoma metastases, and paraffin sections from 98 primary melanomas with the monoclonal antibody 25F9 which recognizes an 86 x 10(3) dalton protein present on a subset of mature human macrophages. Considerable infiltration of tumors with 25F9-positive macrophages was observed in 2 dysplastic nevi (13%), 87 primary melanomas (44%), and 45 metastases (42%). The degree of intratumoral macrophage infiltration correlated with expression of class II HLA-DR antigens on tumor cells, in primary melanoma with a tumor thickness above 0.75 mm, and with the occurrence of metastases within 2 years. In paraffin sections, intratumoral 25F9-positive macrophages also correlated with metastatic spread of primary tumors after longer follow-up. Metastases revealed a higher degree of macrophage infiltration following systemic or local immunotherapy, compared with untreated metastases, or metastases removed during chemotherapy. Of 38 patients who died within an observation period of 1 year, 19 (50%) had considerable infiltration of metastases with 25F9-positive macrophages, whereas this was found in only 4 of 12 patients (33%), who survived for longer than 2 years following metastases removal. A higher degree of 25F9-positive macrophages correlated with a shift towards the T8-positive subsets within the T cell compartment of the infiltrate. Our results suggest that accumulation of 25F9-positive macrophages in melanomas indicates more aggressive tumor properties.
Bröcker
E B
EB
Institute of Experimental Dermatology, University of Münster, Federal Republic of Germany.
Zwadlo
G
G
Suter
L
L
Brune
M
M
Sorg
C
C
D000911:Antibodies, Monoclonal / Q000276:immunology; D000951:Antigens, Neoplasm / Q000032:analysis; D000954:Antigens, Surface / Q000032:analysis; D006684:HLA-DR Antigens / Q000032:analysis; D006801:Humans; D008264:Macrophages / Q000032:analysis / Q000145:classification / Q000473:pathology*; D008545:Melanoma / Q000473:pathology*; D009362:Neoplasm Metastasis; D009506:Nevus / Q000473:pathology*; D010641:Phenotype; D012878:Skin Neoplasms / Q000473:pathology*
D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm; D000954:Antigens, Surface; D006684:HLA-DR Antigens