Feline mammary carcinomas are highly aggressive neoplasms. Several mechanisms are thought to be involved in their progression, including the loss of epithelial adhesion molecules. The present study was carried out on 21 adenomas and 139 mammary carcinomas. Of the carcinomas, 66 were not reported to have metastasized, while the remaining 73 had evidence of regional lymph node metastasis at the moment of diagnosis. The relationship was examined between the expression of the E-cadherin-b-catenin complex and basal (CK5/6, CK14) and luminal (CK8/18) cytokeratin expression. In the medical literature, carcinomas expressing basal cytokeratins are reported as having a poor prognosis in human breast cancer. Results revealed that preservation of the expression of E-cadherin and b-catenin is a significant feature of carcinomas without metastasis, whereas carcinomas with metastasis reveal the loss of one or both adhesion molecules. Additionally, basal cytokeratin expression was statistically associated with the presence of regional metastasis. Furthermore, the expression of E-cadherin-b-catenin was significantly correlated with the high expression of CK18 and low expression of CK5/6.
Keywords feline mammary carcinoma, immunohistochemistry, E-cadherin, b-catenin, basal cytokeratinsMammary neoplasia is the third-most-common tumor type affecting female cats, following hemopoietic neoplasms and skin tumors. Malignancy is frequently reported and presents with local and distant metastases and high mortality rates. 42 Based on age, incidence, risk factors, histopathology, prognostic aspects, metastatic pattern, and response to therapy, feline mammary carcinomas have been proposed as a good model for human breast cancer. 2,42 Similar to reports in women, many veterinary studies describe regional lymph node involvement as one of the most important prognostic factors for feline mammary tumors. 11,16