DAO 58:245-250 (2004)  -  doi:10.3354/dao058245

Metastatic squamous cell carcinoma in two loggerhead sea turtles Caretta caretta

J. Orós1,*, S. Tucker2, L. Fernández3, E. R. Jacobson2

1Unit of Histology and Pathology, Veterinary Faculty, University of Las Palmas de Gran Canaria (ULPGC), and
3Department of Animal Pathology, Veterinary Faculty ULPGC, Transmontana s/n, 35416 Arucas, Las Palmas, Spain
2Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, PO Box 100126, Gainesville, Florida 32610-0126, USA

ABSTRACT: We received 2 stranded loggerhead sea turtles (Caretta caretta) with squamous cell carcinomas to necropsy. The dead turtles had been collected in Gran Canaria and Fuerteventura in April 1994 and May 1997, respectively to determine the cause of death. One turtle had 3 ulcerated lesions in the dorsal part of the neck and several irregular masses in the lungs and kidneys. Histologic examination of lesions in the skin, lungs, kidneys, and ventricular myocardium revealed neoplastic proliferation of abnormal keratinocytes. Ultrastructural examination identified the tumoral cells as epithelial cells. The second turtle had 4 lesions in the skin of the head and flippers, and several irregular masses in the lungs, liver, and kidneys. Histological examination revealed a squamous cell carcinoma with metastases to muscle tissue, liver, lungs, and kidneys. Attempts to characterize the tumoral cells by immunohistochemistry using several monoclonal and polyclonal antisera against high and low molecular weight cytokeratins from mammals, as well as vimentin and desmin, failed. Differences between reptilian keratins (mainly β-keratins) and mammalian keratins (mainly α-keratins) could explain this absence of immunoreactivity. This is the first description of squamous cell carcinoma in sea turtles.


KEY WORDS: Squamous cell carcinoma · Loggerhead turtle · Caretta caretta · Sea turtle · Reptile · Immunohistochemistry


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