Correlation between High Endothelial Vessels and Histopathological Features of Different Pigmented Lesions

Purpose: Tumor infiltrating lymphocytes are playing an important role in cutaneous melanoma being a strong prognostic parameter. Our goal was to study the presence of high endothelial vessels in correlation with the histopathological features in different pigmented skin lesions. Material and methods: our study group included 60 patients (20 cases with dysplastic nevi, 20 thin melanoma and 20 thick melanoma). For each patient we noted epidemiological and clinico-pathological characteristics including: age, gender, anatomic sites, regression, Breslow thickness, mitoses, Clark level and lymphocytic infiltration. Using immunohistochemistry staining we identified the presence of high endothelial vessels in our groups. Results: the most common localization of primary melanoma was trunk 57,5%, followed by extremities 35% and head 7,5%. We found positive MECA-79 vessels in 67% of primary melanoma samples and in 30% of dysplastic nevi. Lymphocytic infiltration was present in 80% samples of dysplastic nevi and 75% of primary melanomas. Using Kruskal Wallis non-parametric test we found a positive association between MECA-79+ vessels and different anatomic sites (p<0,01). We have also found a significant correlation between MECA-79+ vessels and the presence of regression in melanoma samples. In conclusion a better understanding of tumor microenvironment and mechanisms involved in anti-tumor response might play an important role in development of future melanoma therapeutic strategies.