Immunohistochemical Characterization of Hemangiosarcoma in Dogs

摘要

The hemangiosarcoma (angiosarcoma, malignant hemangioendothelioma) is themalignant tumor of the endothelial cells, occuring frequently in dogs and rarely in cats,horses, cows, and sheep (Jubb 2007), having like primary sites especialy the spleen, skin,right atrium, lungs and liver (Brown1985, Robinson,1993). Because of the nonspecific signsand highly methastatic profile the tumors have a poor prognosis when they are diagnosticated.Histologically, the hemangiosarcoma consists of vascular spaces delimitated by anaplastic,elongated, endothelial cells. The vascular spaces contain erythrocytes in variable numbers orthrombi and are delimitated by single or multiple layers of immature, polymorphicendothelial cells. The solid areas of some tumors are presented in small sizes, irregularvascular spaces lined by a single layer of pleomorphic plump, shaped young endothelial cellswith irregular vascular spaces. In the cases in which these characteristics are minimal,immunohistochemistry for CD31/PECAM (platelet endothelial cell adhesion molecule) or forthe VIII factor related antigen (von Willebrand factor) can be used to demonstrate theendothelial derivation and to give an important argument for the further diagnosis ofhemangiosarcoma.In this study we aimed to imunohistochemical characterize all the tumors that werebrought to our department in the last 3 years and that histologically resembled to thecharacteristics of the hemangiosarcoma. The immunohistochemical staining for CD 31 (rabbitpolyclonal to CD31-ab28364) was performed on formalin-fixed paraffin-embedded tissuesusing a strptavidin biotin peroxidase complex method. The immunologic reaction wasdemonstrated using a 0.05% diaminobenzidine tetrahydrochloride in imidazole buffer. Thesections were counterstained with Harriss hematoxylin.From ten tumor cases that were analyzed, in 8 of them we found throughimmunohistochemestry, an expression of CD 31 antigen at the neoplasic cells. In two tumorsthat were histologically alike to the characteristics of the hemangiosarcoma, no expression ofPECAM was found. Even in these cases the hemangiosarcoma is not excluded, for a certaindiagnostic, future immunological characterization of von Willebrand factor and Vimentine isneeded