Metástase de carcinoma mamário em linfonodos regionais de cadelas e seu significado prognóstico

Abstract

Canine mammary tumors are the most common type of neoplasia in bitches. In women, the presence of regional lymph node metastases is an important prognostic factor, and the same is seen in bitches with breast carcinomas. However, the clinical significance of the type of metastasis present in the lymph nodes is still undefined in the canine species. There are also no studies evaluating the influence of lymph node metastasis on survival. Thus, the objective of this study was to evaluate the efficacy of the Immunohistochemistry (IHC) technique in the investigation of isolated tumor cells and hidden micrometastases in comparison to the conventional Hematoxylin-Eosin technique in lymph nodes of bitches with mammary carcinomas; to verify the relation between tumor size, histological type, histological grade and the presence of neoplastic cells in lymph node. Survival of bitches bearing mammary carcinomas with regional lymph node metastases was also evaluated. Fragments of mammary carcinoma and regional lymph nodes of bitches were evaluated for the diagnosis of tumors and the search for tumor deposits and submitted to the IHC test with the use of pan-cytokeratin antibody AE1 / AE3. Spearman rank correlation coefficient test was used to verify the association of tumor size, histological type, histological grade and presence of neoplastic cells in the lymph node. The Kaplan-Meier method was used to calculate the survival curve. Bitches with metastasis have shorter survival, and those with higher metastases have shorter survival than those with lower metastases. Metastatic foci were most commonly seen in the subcapsular lymph node. There was a low correlation between tumor size and the presence of metastasis.