Prognostic factors in canine mammary carcinomas and HER2 expression relationship / Fatores de prognóstico em carcinomas mamários caninos e sua relação com expressão de HER2

Background: The human epidermal growth factor type 2 (HER2) receptor is a membrane glycoprotein tyrosine kinase. In woman, HER2 expression is diagnosed in 30% of breast carcinomas and it is associated with a worse prognosis, higher rate of recurrence and mortality. In the bitch, the HER2 overexpression in canine mammary tumors is still controversial and the prognostic value remains uncertain. Thus, we aimed to verify the HER2 expression in canine mammary carcinomas and relate it to the type and histological grade, lymph node metastasis and clinical staging. Materials, Methods & Results: Ninety bitches diagnosed with mammary carcinoma were included in this study. The inclusion criteria were bitches with complete clinical examination, thoracic radiographic examination and submitted unilateral or bilateral mastectomy. Ninety-nine samples of mammary carcinoma were used and the fragments of tumor and regional lymph nodes were fixed in 10% neutral formalin for histopathological and immunohistochemistry analysis. The lesions were evaluated by two pathologists and classified according to the type and histological grade. HER2 expression was performed by semi-quantitative analysis of the slides according to the HerceptTestTM (Dako) recommended score. Simple carcinomas were the most frequent (51.51%) followed by complex carcinomas (46.47%) and in situ carcinoma (2.02%). [...](AU)

Prognostic factors in canine mammary carcinomas and HER2 expression relationship / Fatores de prognóstico em carcinomas mamários caninos e sua relação com expressão de HER2

Background: The human epidermal growth factor type 2 (HER2) receptor is a membrane glycoprotein tyrosine kinase. In woman, HER2 expression is diagnosed in 30% of breast carcinomas and it is associated with a worse prognosis, higher rate of recurrence and mortality. In the bitch, the HER2 overexpression in canine mammary tumors is still controversial and the prognostic value remains uncertain. Thus, we aimed to verify the HER2 expression in canine mammary carcinomas and relate it to the type and histological grade, lymph node metastasis and clinical staging. Materials, Methods & Results: Ninety bitches diagnosed with mammary carcinoma were included in this study. The inclusion criteria were bitches with complete clinical examination, thoracic radiographic examination and submitted unilateral or bilateral mastectomy. Ninety-nine samples of mammary carcinoma were used and the fragments of tumor and regional lymph nodes were fixed in 10% neutral formalin for histopathological and immunohistochemistry analysis. The lesions were evaluated by two pathologists and classified according to the type and histological grade. HER2 expression was performed by semi-quantitative analysis of the slides according to the HerceptTestTM (Dako) recommended score. Simple carcinomas were the most frequent (51.51%) followed by complex carcinomas (46.47%) and in situ carcinoma (2.02%). [...]