Abstract

This paper presents a case report of canine ovarian adenocarcinoma, detailing its pathological diagnosis to serve as a reference for the pathological evaluation of this tumor in canines. A routine clinical workup was conducted on the affected dog. The animal exhibited decreased appetite and diarrhea prior to presentation. Physical examination via palpation revealed a markedly increased abdominal circumference, with a palpable free hard mass in the abdomen and absence of pain response. Abdominal ultrasonography demonstrated significant amounts of ascites, uterine fluid accumulation, and marked enlargement of the left ovary. Subsequent laparotomy identified numerous neoplastic masses involving the liver, gastric wall, greater omentum, and uterine cavity. Histopathological analysis of the excised tumor revealed distinct morphological features. Microscopically, the neoplasm exhibited papillary architecture projecting into the lumen, with infiltration and expansion into the ovarian stroma. Focal serous cysticlike structures were observed within the tumor. Tumor cells were cuboidal with hyperchromatic nuclei, displaying coarsely clumped chromatin, prominent nucleoli, and numerous atypical mitotic figures. Focal areas of necrosis, calcification, and stromal fibrosis were also noted. The omental tumor tissue exhibited identical histological characteristics to the ovarian primary tumor. Immunohistochemical staining further supported the diagnosis, showing positive CK7 expression and negative INHa expression in tumor cells, consistent with canine ovarian adenocarcinoma. Conclusion: Based on histopathological examination, immunohistochemical staining, and intraoperative findings, the left ovarian mass in this canine was diagnosed as ovarian adenocarcinoma.

Keywords:Canine; Ovarian adenocarcinoma; Pathological Diagnosis; Histopathology; Immunohistochemistry