Cytopathological and immunohistochemical assessment of mammary tumors in male dogs

Abstract

Three male dogs affected with mammary tumors brought for treatment were aged 7 to 10 years. Tumor was noted at right caudal thoracic in one dog and left caudal thoracic region in two dogs. The mean haemato-biochemical parameters revealed no alterations except leucocytosis associated neutrophilia and elevated blood urea nitrogen and creatinine. The serum sex hormones estradiol and progesterone were increased, whereas, testosterone values were unaltered. Grossly, cut surface of the tumor mass from one dog revealed greyish white, blood tinged and cauliflower like growth. Fine needle aspiration smears revealed neoplastic cells mixed with inflammatory cells. Histopathologically the tumor mass revealed extensive proliferation of dense fibrous tissue, area of chondroid differentiation and transformation of fibroblast into cartilage. Proliferating neoplastic cells showed degeneration, necrosis and infiltration of inflammatory cells. Immunohistochemical analysis of tumor tissues revealed triple negative phenotype for estrogen and progesterone receptors and Human Epidermal Growth Factor-2, but positive reaction for cytokeratin. Clinico-pathological investigations and immunohistochemical features were consistent in diagnosis of mammary tumors in male dogs.