Diffuse Large B-Cell Lymphoma (DLBCL) in an Aged Raccoon (Procyon lotor)

A 15-years-old, captive, female raccoon (Procyon lotor) was necropsied after a one-week history of apathy and self-isolation. Gross changes consisted of the severe enlargement of the mesenteric lymph node; hepatosplenomegaly with multifocal to coalescing, white tan nodules in the spleen and liver,; and pale kidneys. Histologically, neoplastic CD79α-positive lymphocytes effaced the mesenteric lymph node and multifocally infiltrated the spleen, liver, and kidneys, and focally infiltrated the heart. Based on pathological and immunohistochemical findings, as well as the canine-adapted World Health Organization (WHO) diagnostic criteria, a diagnosis of diffuse large B-cell lymphoma (DLBCL) was made.