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

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 and anti-multiple myeloma oncogene 1 (MUM-1) for plasmacytoma confirmed this neoplasm to be of B-cell origin. This is the first recorded case of a plasmacytoma in a harbor porpoise. Routine viral screening was negative via standard PCR for herpesvirus and reverse transcriptase PCR for morbillivirus. Retroviral screening was not performed.

Persistent Organic Pollutant and Hormone Levels in Harbor Porpoise with B Cell Lymphoma.

B-cell lymphoma, a common morphologic variant of non-Hodgkin lymphoma, has been associated with persistent pollutants in humans, but this association is not well-characterized in top-level predators sharing marine resources with humans. We characterized and compared blubber contaminants and hormones of a pregnant harbor porpoise (Phocoena phocoena) with B-cell lymphoma, with those in two presumed healthy fishery by-caught porpoises with no lymphoma: a pregnant adult and female juvenile. Common historic use compounds, including polychlorinated biphenyls, polybrominated diphenyl ethers, and pesticides, were evaluated in blubber samples from three porpoises. In addition, blubber cortisol and progesterone levels (ng/g) were determined in all three animals. Total pollutant concentrations were highest in the juvenile porpoise, followed by the lymphoma porpoise and the nonlymphoma adult. Blubber cortisol concentrations were 191% greater in the pregnant with lymphoma porpoise compared with the pregnant no lymphoma porpoise, and 89% greater in the juvenile female compared with the pregnant no lymphoma porpoise. Although both adults were pregnant, progesterone levels were substantially greater (90%) in the healthy compared with the lymphoma adult. Health monitoring of top-level marine predators, such as porpoise, provides a sentinel measure of contaminants that serve as indicators of potential environmental exposure to humans.