Relationships Between the Microvascular Network and Mast Cell Density in Malignant Melanoma

Background and Objectives: Angiogenesis plays an important role in many types of cancers, including melanoma. Mast cells are among the most important cellular partners involved in the angiogenic process. The purpose of the present study is to establish the interrelations between microvessels and mast cell density, and to describe the prognostic role of mast cells in malignant melanoma. Materials and Methods: A total of 92 cases of melanoma were evaluated. Hematoxylin-eosin staining and CD34/mast cell tryptase double immunostaining were performed. Results: Of the cases, 28 were classified as T1 (30.43%), 31 as T2 (33.69%), 21 as T3 (22.82%), and 12 as T4 (13.04%). Mast cells were mainly located in the infiltrate area in cases with inflammatory infiltrate. Few mast cells were observed in the absence of infiltrate. A granular type was observed in intratumoral areas with an isolated and perivascular distribution of mast cells. A significant correlation was found between intratumoral MVD and intratumoral MCD (mast cell density) in T1 and T4 melanoma cases (p = 0.0001 and p = 0.0029, respectively). In T2 cases, significant correlations were found between intratumoral and peritumoral MVD and G (p = 0.0169, p = 0.0003), between intratumoral MCD and MVD (p = 0.0041), and between peritumoral MVD and the number of peritumoral mast cells (p = 0.0011). T3 cases showed a significant correlation between the density of intratumoral mast cells and peritumoral ones (p = 0.001); between the MVD and mast cell density of the intratumoral area (p = 0.0001); between the intratumoral MVD and peritumoral mast cell density (p = 0.0001); between the MVD and mast cell density of the peritumoral area (p = 0.0325); and between the peritumoral MVD and intratumoral mast cell density (p = 0.0458). Conclusions: Both intratumoral and peritumoral mast cells were found to participate in melanoma progression, and they showed greater involvement in the early phases of angiogenesis in malignant melanoma.