Novel Thoracentesis Technique and Diagnosis of Metastatic Cholangiocarcinoma in an Atlantic Bottlenose Dolphin (Tursiops truncatus)
1Tequesta, FL, USA; 2Department of Comparative, Diagnostic, and Population Medicine, College of Veterinary Medicine, University of Florida, Gainesville, FL, USA; 3Veterinary Diagnostic Laboratory, College of Veterinary Medicine, University of Illinois, Urbana, IL, USA; 4Independent, Key Largo, FL, USA; 5Veterinary Consulting, Jupiter, FL, USA
Abstract
An approximately 12–14-year-old Atlantic bottlenose dolphin (Tursiops truncatus) that had stranded 12 years prior and was deemed non-releasable, presented with anorexia and acute azotemia. Ultrasound evaluation identified bicavitary free fluid accumulation (originally thought to have resulted from aggressive fluid therapy for azotemia), an apparent mass in the area of the pancreas, markedly irregular pleura, and a consolidated left lung. Thoracentesis was performed for therapeutic and diagnostic benefits. Thoracentesis techniques in bottlenose dolphins historically utilize a 1½”–2¼” IV catheter with stylet or standard needle to penetrate the thoracic cavity under ultrasound guidance.1,2 During this procedure, a TurkelTM Safety Thoracentesis Needle was used under ultrasound guidance to decrease the risk of potential complications. The animal tolerated the procedure well and his respiratory rate decreased after removal of 3 liters of free thoracic fluid. The sampled fluid was pale yellow and clear with frequent small white floccules and cytologically was consistent with a neoplastic effusion due to carcinoma. Euthanasia was performed due to poor prognosis and further clinical decline. On gross necropsy there were multiple tan, firm nodules throughout the lungs, mediastinal pleura, marginal lymph nodes, as well as in the liver, pancreas and mesenteric lymph nodes. Histopathological evaluation was consistent with cholangiocarcinoma and multicentric metastasis. This is the first report of cytological diagnosis of carcinoma via pleural effusion in a cetacean and of cholangiocarcinoma in a marine mammal in managed care. One other case was recently reported in a stranded harbor porpoise.3
*Presenting author
Literature Cited
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