Spontaneous Malignant T Cell Lymphoma in a Young Male Common Marmoset (<i>Callithrix jacchus</i>)

Abstract

We histopathologically and immunohistochemically investigated a case of malignant lymphoma that spontaneously developed in a male common marmoset at two years of age. Beginning at two years four months of age, the animal had an enlargement of the submandibular and inguinal lymph nodes, small subcutaneous nodules near the right breast and an approximately fivefold increase in peripheral lymphocyte count compared with the previous examination value. The postmortem findings at two years eight months of age showed lymphadenopathy with enlargement of the thymus and spleen. Small- to intermediate-sized neoplastic lymphocytes had diffusely proliferated in the enlarged nodes. The neoplastic cells were pleomorphic and had irregularly shaped nuclei. The nuclear chromatin staining revealed hyperchromatism in the small-sized cells, and the intermediate-sized cells exhibited vesicular staining. An immunohistochemical examination indicated that the neoplastic lymphocytes were positive for CD3 and negative for CD20, thus suggesting that they had originated from T cells. In addition, the proliferation of high endothelial venules and reactive epithelioid histiocytes was observed. Scattered tingible body-laden macrophages were infrequently detected. Neoplastic lymphocytes were also observed in the thymus, spleen, heart, lungs, liver, kidneys, adrenal glands and femoral and sternal bone marrow. This malignant lymphoma in a young male common marmoset was considered to fit the category of “peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS)” according to the new WHO system of classification.

Causes of death in neotropical primates in Rio Grande do Sul State, Southern Brazil

“…Lymphoid neoplasms have been described in nonhuman primates, mainly in Old World primates 25,27 . Although the occurrence of spontaneous lymphoma has been reported in New World species, it is considered a rare event, 27‐29 similarly to that evidenced in the current work.…”

Spontaneous disseminated T‐cell lymphoma in a buff‐headed capuchin (Sapajus xanthosternos)

“…ateles , 5 and Epstein‐Barr virus 13 . Spontaneous lymphoma has been described in a common marmoset ( Callithrix jacchus ) and tamarins ( Saguinus oedipus , Saguinus mystax ) 3,14 …”

“…Reports of spontaneous hematopoietic neoplasms in Platyrrhines species are scarce. The lymphoma oncogenesis in humans and nonhuman primates is often correlated with virus infection 3 …”

“…The lymphoma oncogenesis in humans and nonhuman primates is often correlated with virus infection. 3 The Herpesviridae is an oncogenic family, especially Herpesvirus saimiri, H. ateles, and Epstein-Barr virus can induce lymphomas in neotropical primates. [4][5][6] Herein, we present the gross, histopathological, and immunohistochemical findings of spontaneous disseminated T-cell lymphoma in a Buff-headed Capuchin (Sapajus xanthosternos).…”

Spontaneous pulmonary adenocarcinoma in a common marmoset (Callithrix jacchus)

“…The common marmoset ( Callithrix jacchus ) is a New World primate that has been increasingly used in research, including biomedical 1‐3 and aging research 3,4 . However, there have been few case reports regarding spontaneous neoplasms, such as lymphoma, 5 small intestinal adenocarcinoma, 6 and rhabdomyosarcoma 7 …”