Lymphosarcoma with leukemic blood profile in a Savannah monitor lizard (Varanus exanthematicus)

A 6-mo-old male Savannah monitor lizard (Varanus exanthematicus) was presen ted for lethargy and anorexia of 7 days duration. Physical examination reve aled a slightly raised subcutaneous mass (1 cm diameter) in the left scapul ar area. Fine-needle aspiration cytology of the mass revealed a population of immature, pleomorphic lymphoid cells consistent with lymphosarcoma. A he mogram indicated marked leukocytosis (465,000 cells/mu l) characterized by extreme lymphocytosis and many circulating lymphoid blast cells. The lizard was euthanized at the owner's request. Necropsy revealed severe hepatomega ly and multiple raised, ulcerated mural mosses in the gastrointestinal trac t. There were many raised, poorly demarcated tan foci in all the parenchyma l organs. Histopathologic examination confirmed infiltration of all parench ymal organs by neoplastic lymphoid cells. Transmission electron microscopic examination failed to identify viruses within the neoplastic cells. A lite rature review revealed few reports of squamate leukemia and lymphosarcoma a nd none in Savannah monitor lizards.