Expression of the Vascular Marker CD31 in Dog Cutaneous Melanoma

摘要

Vasculogenic mimicry, as previously described in aggressive melanoma, is characterized by the novo generation of intratumoural patterned vascular channels, providing additional microcirculation, in support to the classic tumoural angiogenesis.In this work we investigated the immunohistochemical expression endothelial marker, CD31, in tumour tissues of 5 dog cutaneous melanomas and 2 dog cutaneous melanocytomas as possible evidence of vasculogenic mimicry. In addition we investigated the relationship between CD31 expression and mitotic activity.For the investigated cases, 6 were positive (1 melanocytoma, 5 melanomas), and 1 case was negative (melanocytoma), in melanoma cases, a positive correlation between mitotic index figures and microvessel density in high field power (3 cases) was found. In melanomas was also found a high percentage of vessels/total area mainly in tumours with low of mitotic index figures (4 cases). High microvessel density was found also in one melanocytoma.In conclusion, CD31 immunoreactivity generally increase related to high number of mitotic index figures (3 cases). In melanomas high percentage of vessels/total area with low of mitotic index figures (4 cases) was found