This breast tumor may now be considered as a distinct type made up of a cyst or dilated duct into which projects a soft, friable, papillomatous growth. In occasional cases in the same breast, or in the wall of the cyst, definite carcinoma is present with invasive and metastatic properties. In the literature the condition is referred to under various names—adenoma, villous papilloma, duct papilloma, cystadenoma papillae, polycystoma proliferum, proliferating cystadenoma, papillary cystoma, duct cancer and carcinome villeux. With these is often described another tumor of common occurrence, but one that only rarely takes a form that could be confused with the true papilloma. This growth shows a cauliflower-like projection into the cyst, rather than the soft, friable, delicate branchings of the primarily epithelial structure. It is referred to as cystadenoma intracanaliculare, intracanalicular cystadenoma or myxoma, and endocanalicular papillary fibroma. We have been accustomed to call this the intracanalicular fibro-adenoma