CHARACTERIZATION OF PROSTATIC BASAL-CELL HYPERPLASIA AND NEOPLASIA INAGED MACAQUES - COMPARATIVE PATHOLOGY IN HUMAN AND NONHUMAN-PRIMATES

There are very few reports of proliferative prostatic lesions occurrin g spontaneously in nonhuman primates. We found that 15 of 19 glands in aged macaques contained one or more epithelial lesions in the cranial lobe. These originated in the basal cell compartment and were charact erized as hyperplasia and benign neoplasia. The adenomas contained var iable gland formation, with morphologic and immunohistochemical eviden ce of secretory, mucigenous, neuroendocrine, transitional, and squamou s cell differentiation. These cell types are resident in the normal pr ostate or appear in metaplastic lesions, and their presence in the mac aque tumors is consistent with differentiation of a stem cell along mu ltiple phenotypic pathways.:The macaque growths are similar to human p rostatic basal cell lesions and could provide insights into their path ogenesis as well as cellular ontogeny and general mechanisms of carcin ogenesis in this organ. (C) 1996 Wiley-Liss, Inc.