J Vet Diagn Invest 20:656–660 (2008) Diffuse intestinal T-cell lymphosarcoma in a yellow-naped Amazon parrot (Amazona ochrocephala auropalliata)

Abstract. A 10-year-old, intact, female yellow-naped Amazon parrot (Amazona ochrocephala auropalliata) was examined because of anemia, lymphocytic leukocytosis, regurgitation, and weight loss. A positive fecal occult blood and monoclonal globulinopathy were present. A distended proventriculus and diffusely thickened loops of small intestine with irregular luminal surfaces were identified with contrast radiography and contrast computed tomography. A micro positron emission tomography scan was performed with 18F-fluoro-deoxyglucose. Diffuse intestinal T-cell lymphosarcoma was diagnosed based on histopathology and immunohistochemistry of full thickness small intestinal biopsies. The patient was treated with a multidrug chemotherapy protocol with little to no effect. Euthanasia was elected, and intestinal lymphosarcoma was confirmed on histopathology of necropsy intestinal samples; no other organs demonstrated neoplastic infiltration. To the authors ’ knowledge, no reports are currently available detailing the clinical presentation or diagnosis of diffuse intestinal T-cell lymphosarcoma in any avian species. Key words: Avian; immunohistochemistry; lymphosarcoma; positron emission tomography. 1 Lymphosarcoma (LSA) is the most commonly reported lymphoid neoplasm in parrots and has been reported i