A case of T-cell chronic lymphocytic leukemia progressing to Richter syndrome with central nervous system involvement in a dog

Conway, E. A. , Waugh, E. M. and Knottenbelt, C. (2020) A case of T-cell chronic lymphocytic leukemia progressing to Richter syndrome with central nervous system involvement in a dog. Veterinary Clinical Pathology, 49(1), pp. 147-152. (doi: 10.1111/vcp.12839) (PMID:32215932)

Abstract

An 8‐year‐old neutered Beagle dog was presented with polyuria and polydipsia. Routine clinicopathologic testing showed a significant lymphocytosis and proteinuria. Lymphocytes were of small to intermediate in size with a mature morphology. Infectious disease screening was negative. PCR for antigen receptor gene rearrangements showed a clonal T‐cell receptor (TCR) rearrangement consistent with T‐cell chronic lymphocytic leukemia (CLL). Bone marrow cytology showed <30% lymphocytes, while the proportion in splenic fine‐needle aspirate cytology was considered increased. The dog was initially monitored but started on prednisolone and chlorambucil therapy 2 months later due to worsening clinical signs and progressive lymphocytosis. After an additional 2 weeks, the dog developed multifocal spinal pain and single‐node lymphadenomegaly. Cytology of the lymph node showed a monomorphic population of large lymphoblasts consistent with lymphoma. Cytology of a cerebrospinal fluid sample also showed large lymphoblasts. PCR for antigen receptor gene rearrangement at both sites showed a clonal TCR rearrangement of the same molecular size as in the initial leukemic cells. The dog was diagnosed with a transformation of the CLL to Richter syndrome (RS) with involvement of the central nervous system (CNS). Therapy was started with L‐asparaginase and an increased dose of prednisolone; however, the dog was euthanized due to progressive clinical signs. To our knowledge, this is the first report of canine RS with direct involvement of the CNS.

• Item Type: Articles
• Keywords: General Veterinary
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Conway, Dr Elizabeth and Knottenbelt, Professor Clare and Waugh, Ms Elspeth
• Authors: Conway, E. A., Waugh, E. M., and Knottenbelt, C.
• College/School: College of Medical Veterinary and Life Sciences > School of Biodiversity, One Health & Veterinary Medicine
• Journal Name: Veterinary Clinical Pathology
• Publisher: Wiley
• ISSN: 0275-6382
• ISSN (Online): 1939-165X
• Published Online: 25 March 2020
• Copyright Holders: Copyright © 2020 American Society for Veterinary Clinical Pathology
• First Published: First published in Veterinary Clinical Pathology 49(1):147-152
• Publisher Policy: Reproduced in accordance with the publisher copyright policy