Invasive micropapillary carcinoma of the dog mammary gland: a case report

This report describes the morphological and immunohistochemical findings of two cases of breast invasive micropapillary carcinoma occurring in dogs. Histologically, the tumors are characterized by the presence of numerous irregular cystic formations filled out with nests of epithelial cells that exhibit a micropapillary pattern. These morphological features are characteristic of invasive micropapillary carcinoma in woman, a breast tumor not previously described in dogs