A case report on metastatic mammary gland carcinoma in a cat: combined radiography and cytology-based approach

Abstract

Mammary gland carcinoma is the third most frequent aggressive feline neoplasm that usually occurs in senile, female cats with an age ranging between 10 and 14 years and a poor prognosis. In this study, we examined a 14-year-old non-spayed female Calico cat, presented with a mammary gland tumor at Teaching & Training Pet Hospitals and Research Center, Dhaka. After a comprehensive assessment of clinical history and physical examinations non-pruritic, small nodular mass (>6 cm), surrounding the nipple of the inguinal right mammary gland was observed. Regional pain was noted during palpation, and the subcutis was firm. Therefore, the mass was subjected to a fine needle aspiration biopsy for cytological study. Mammary gland carcinoma was diagnosed initially based on the presence of cellular aggregates with neoplastic features, such as anaplastic cells with bizarre nuclei and multinucleated pleomorphic cells, suggesting a high degree of malignancy using PAP staining. Subsequently, radiographic image was taken from the thoracic and abdominal region to understand the aggressive pattern of the tumor or any metastatic lesions. A radiographic image showed a 7x5x4 cm mass that affected the position of various organs, and a nodular mass was also observed in the lungs. Furthermore, thoracocentesis was done for FNAC from lung tissue, and similar neoplastic cells were identified which clearly indicates the metastasis stage. Therefore, it was challenging to make any decision for a local excision due to the metastasis in the visceral organ and grave prognosis. However, the surgeon also did not agree about opting for a local surgical procedure due to potential pain and the uncertainty of its success as the cat was not fit for surgical stress or anesthetic procedures. Moreover, we have no facility for radiotherapy or chemotherapy treatment for malignant tumors in cats. So, understanding the overall condition of the cat and its therapeutic limitations and grave prognosis the owners finally decided on euthanasia. For performing euthanasia, firstly a sedative agent (Xylazine) was administered with a dose of 1mg/kg body weight. Then an injection with an overdose (60 mg/kg body weight) of thiopental sodium is used and the cat loses consciousness quickly without showing any pain symptoms and death occurred within a few moments