Pituitary adenoma with galactorrhea in an adult male cynomolgus macaque (Macaca fascicularis).

Although endocrinopathies in many animal species are well documented, an adult, male, wild-caught cynomolgus macaque (Macaca fascicularis) presented an interesting diagnostic challenge. Previous physical examinations had been unremarkable with the exception of a heart murmur. The animal presented with ulcerative dermatitis in the dorsal cervical area, and physical exam revealed white material around the nipples. A white milky substance could be expressed bilaterally from the nipples. Hematologic, serologic, and urine samples revealed glucosuria, ketonuria, and hyperglycemia. Further diagnostic testing confirmed persistent hyperglycemia and revealed elevated serum prolactin and cortisol levels. During subsequent imaging studies, the animal underwent cardiac arrest and was euthanized. Gross necropsy findings included an enlarged pituitary gland. A prolactin-secreting pituitary adenoma was confirmed on histopathology. In light of the results of serum biochemical analyses, the additional diagnosis of type II non-insulin-dependent diabetes mellitus was made. This case represents the first documented antemortem diagnosis of a prolactin-secreting pituitary tumor in a cynomolgus macaque.