Mammary adenocarcinoma in Wistar rat - A case report

This paper describes a spontaneous case of mammary adenocarcinoma in a 12 week old female Wistar rat. At necropsy, all organs appeared normal except the presence of growth in the ventral abdomen subcutaneous region, which was greyish white in colour. Microscopically, the growth revealed the features of mammary adenocarcinoma consisting of papillary, tubular, cribriform and comedo patterns. Neoplastic cells were arranged in one to several layers thickness with few glandular structures interspersed in stromal tissues. Nuclei had numerous mitotic figures and clumped chromatin. Stromal tissues were composed of broad connective tissue bundles, and revealed mononuclear cells infiltration and newly formed blood vessels.