Spontaneous Malignant Lymphoma in a New-World Primate

A spontaneous hematopoietic neoplasm in a cotton-top marmoset (Saguinus oedipus) was characterized by perivascular infiltration and invasion of the liver, kidneys, adrenals, spleen, lymph nodes, bone marrow, and lungs by a pleomorphic primitive reticular cell. A significant fraction of the circulating white cells was of the same cell type. The disease was diagnosed as lymphosarcoma of the reticulum-cell type with features similar to viral-induced malignancy previously described. There are few reports of spontaneous hematopoietic neoplasms in nonhuman primates. According to a recent survey, only 21 cases have been reported (1). The marmoset is a small new-world primate that has been investigated extensively as a possible animal model for the study of several important human diseases (2, 3), including cancer (4, 5). Recently HUNTet al. (6) induced a disease closely resembling malignant lymphoma in the marmoset (Saguinus oedipus) and the owl monkey (Aotus trivirgatus) by the adminis­ tration of Herpesvirus saimiri. The spontaneous occurrence in a cotton-top marmoset (Saguinus oedipus) of a disease with many features consistent with malignant lymphoma and with most of the manifestations of the disease that was induced by HUNTet at. (6) is discussed.