TUMOR-INFILTRATING CD1A+ LANGERHANS CELLS IN PRIMARY CUTANEOUS MELANOMA – AN IMMUNOHISTOCHEMICAL STUDY
We highlight in this paper the main immunological roles of dendritis cells (DCs) in cancer, specifically in melanoma. The presence of dendritic cells in the tumor microenvironment triggers an effective antitumor immunity by recruiting of infiltrating tumor lymphocytes. Moreover, DCs also have the role of regulating and maintaining immune responses. DCs are present in both normal skin and melanocytic skin lesions. At the normal skin level, DCs are predominantly in the epidermis with few located in the dermis and few others that migrate in the circulation. However, in melanocytic lesions such as benign and dysplastic nevi, an increase in the density of DCs in the dermis is observed, with coexpression of CD1 and S100 markers. The aim of the study is to investigate CD1a expression in primary cutaneous melanoma. Regarding this, we conducted a retrospective transverse study of 37 cases of primary superficial spreading melanoma. We analyzed the clinical and histopatogica aspects of our group of study and we performed some correlations between CD1a expression and clinical and histopathological parameters. These correlations were tested using nonparametric tests such as Pearson and Spearman tests. The threshold for p values was considered statistical significant for 0.05. After performing Pearson test we found that CD1a positivity correlates statistically with Breslow index (p=0.017, r=0.434), Clark level (p=0.012, r=0.454), mitotic rate (p=0,036, r=0,390) and the ulceration of the tumor (p=0.044, r=0.370), with a moderate statistical power. Spearman test also showed positive correlation between CD1a expression and Breslow thickness (p=0,001, Sperman’s rho=0,593), Clark level (p=0,10, Sperman’s rho=0,465) and tumor ulceration (p=0,033, Sperman’s rho=0,391).
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