Hepatic B‐cell lymphoma in a wild European badger ( Meles meles ) in the UK

Abstract Neoplastic diseases are considered rare in wild European badgers ( Meles meles ) with a single pelioid hepatocellular carcinoma, and four lymphoma cases (two T‐cell, two unclassified) in the literature. A found‐dead, elderly, male wild badger underwent postmortem examination for Mycobacterium bovis surveillance. The carcase was icteric and cachexic. There were multifocal white‐to‐cream firm nodules throughout the parenchyma of the liver (primary site), kidney and spleen, alongside a mild mesenteric lymphadenopathy. Mycobacterial cultures were negative. A population of small neoplastic lymphocytes were identified in the liver, kidney and spleen (CD79a + , CD20 + , PAX‐5 + and CD3 − ). BLASTP identities range from 57.14% (CD3) to 100% (CD79a). The neoplastic population had specific but faint Ki67 immunolabelling (index 37.4). This case was consistent with a primary hepatic, small‐cell B‐cell lymphoma with a low‐to‐medium histological grade. To the best of the authors’ knowledge, PAX‐5 and CD20 have not previously been used in badgers and could complement future research.