Abstract

A 13-year-old female jaguar, Panthera onca, who was implanted with multiple melengestrol acetate implants for approximately 7 years, was diagnosed with a uterine mass based on ultrasonographic finding after a history of hematuria, anorexia, and weight loss. An ovariohysterectomy was performed, and histology revealed a uterine adenocarcinoma with severe diffuse pyometra and multifocal metritis. Based upon the invasive nature of the tumor on histopathology and previous reports of metastasis documented in domestic and wild felids, it was presumed that this tumor had the potential for metastasis, warranting the administration of chemotherapy. Prior to starting treatment, a complete blood count, serum biochemistry, thoracic radiographs, abdominal ultrasound and echocardiogram were performed evaluating the overall health and suitability of chemotherapy for this patient.

The protocol chosen for the jaguar was based on the one set forth by Kissiberth using carboplatin in tumor-bearing cats.¹ Carboplatin chemotherapy (TEVA pharmaceuticals, Sellersville, PA, USA) was initiated at a dosage of 180 mg/m² IV at 4–5-week intervals for 5 treatments. Side effects were graded as mild to moderate using the (VCOG-CTCAE) as a guideline.

Approximately 20 months from diagnosis, the animal was found dead. On necropsy, animal’s death was presumed to have been due to liver failure, which appears to be unrelated to the chemotherapeutic protocol. Neoplasia was not detected on gross or histopathology, indicating complete remission. Carboplatin at a dosage of 180 mg/m² IV at 4–5-week intervals for 5 treatments appears to be an effective and well-tolerated protocol in jaguars.

Acknowledgments

The authors wish to thank the staff of the BREC Baton Rouge Zoo and the Diagnostic Imaging Department and Oncology Department of Louisiana State University School of Veterinary Medicine.

Literature Cited

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