Endometrial Mucinous Adenocarcinoma in a Bitch With Pyometra—A Case Report

Endometrial adenocarcinomas present rare neoplasia of bitches. This case report describes mucinous endometrial adenocarcinoma in a bitch with concurrent pyometra for the first time. A mass on the uterine stump was removed during surgery of a 13-year-old bitch with clinically suspected pyometra. Histopathology revealed mucinous endometrial adenocarcinoma. The tumor was classified according to human classification, responding to women's type I (endometrioid carcinoma). Immunohistochemistry showed a positive expression of estrogen receptor α, progesterone receptor, p53, and p16 gene, while vimentin was not expressed.