S Hesaraki - Department of Pathology, Science and Research Branch, Islamic Azad University, Tehran, Iran

BACKGROUNDS: Seminoma is frequently observed in human and canine testes especially in cryptorchids. Canine and human seminomas are typically associated with leukocytic infiltration. OBJECTIVES:We aimed to identify the type of lymphocytes that infiltrate to seminomas. METHODS: Tumor infiltrating lymphocytes were evaluated by immunohistological techniques in 5 dogs with diffuse seminoma. Routine pathological examination of these specimens showed diffuse seminoma with tumor infiltrating lymphocytes in all cases. RESULTS: Lymphocytes in seminomas were predominantly T cytotoxic (CD3+, CD8+) cells. These cells were distributed diffusely, but patchy around the vessels. B-cells were also identified as some rare single cells diffusely scattered in the tumoral parenchyma.CONCLUSIONS:The results of this study showed that the lymphocyte infiltrating cells are mainly T lymphocytes particularly CD8 cytotoxic type.

lymphocyte,seminoma,immunohistochemistry, canine