Mammary carcinoma in a male rhesus macaque (Macaca mulatta) : histopathology and immunohistochemistry of ductal carcinoma in situ

Background A mammary nodule was noted in a male rhesus macaque during physical examination. Methods and Results Histopathological and immunohistochemical analysis was performed. Ductal carcinoma in situ was confirmed. Conclusions To date, there are two reports of mammary carcinoma in male non-human primates, and none in the rhesus macaque.