Naturally Occurring Peripheral T-cell Lymphoma Not Otherwise Specified (PTCL-NOS) with Systemic Dissemination in a Beagle

Abstract

A 6-year-old intact female Beagle dog presented with acute vomiting. Abdominal ultrasound showed abdominal lymphadenopathy, ascites and a hyperechoic mass within the pancreas. Thoracic radiographs and echocardiography revealed cardiomegaly with pericardial effusion. The dog died following rapid deterioration and a subsequent necropsy revealed a multilobulated white-to-tan mass within the pancreas, attaching to the omentum, stomach and left adrenal gland. The heart was enlarged and infiltrated by similar coalescing off-white irregular masses. Histologically, the masses consisted of infiltrative sheets of large T lymphocytes replacing the normal architecture of the heart along with the lymph nodes, pancreas, stomach, omentum, left adrenal gland, right ovary, heart, liver, gall bladder as well as the lungs and eyes. Based on histomorphology and immunophenotyping, this case was diagnosed as peripheral T-cell lymphoma not otherwise specified (PTCL-NOS) with systemic dissemination to unusual sites including the heart.