Pheochromocytoma in six New World primates

Six New World primates, including 2 golden lion tamarins (Leontopithecus rosalia), 2 cotton-top tamarins (Saguinus o. oedipus), 1 black howler monkey (Alouatta caraya), and 1 black-handed spider monkey (Ateles g. geoffroyi), were diagnosed with unilateral (4/6) or bilateral (1/6) adrenal or extra-adrenal (1/6) pheochromocytoma by light microscopy and immunohistochemical staining for chromogranin A. Overt invasive behavior or metastases were not observed in any primate, and thus these neoplasms were considered benign. All primates either died spontaneously (4/6) or were euthanatized (2/6) as a result of concurrent malignant neoplasia, infection, renal disease, or a combination of several disease processes. Although we did not determine whether these pheochromocytomas were functional, all 6 primates had myocardial fibrosis, and some had arteriosclerosis.