DAO prepress abstract  -  DOI: https://doi.org/10.3354/dao03204

Multicentric plasmacytoma in a harbor porpoise Phocoena phocoena off the Coast of Whidbey Island, Washington State, USA

Barry H. Rickman*, Tim Morgan, Matthew Klope, Susan Berta, Sandra Dubpernell, Howard Garrett, Mary Jo Adams, Stephanie A. Norman

*Email: barry.rickman@gmail.com

ABSTRACT: Necropsy of a female adult pregnant harbor porpoise Phocoena phocoena revealed a multicentric plasmacytoma. The plasmacytoma infiltrated the cranial lung lobes, mediastinal lymph nodes and the spleen. Diagnosis was based on gross, histopathologic, and immunohistochemical studies. Histopathology revealed a diffuse proliferation of atypical pleomorphic neoplastic round cells with plasmacytic features. Positive immunohistochemistry with anti-CD79a and anti-CD20 antibody markers confirmed this neoplasm to be of B-cell origin, and anti-Mum-1 positivity for plasmacytoma. This is the first recorded case of a plasmacytoma in a harbor porpoise. Routine viral screening was negative via standard polymerase chain reaction (PCR) for herpesvirus and reverse transcriptase PCR for morbillivirus. Retroviral screening was not performed.