This is a whole mount of an intraductal papilloma. Usually, but not always, these lesions are not large enough to photograph as a gross specimen, something you would easily see with the naked eye. This papilloma resides in a dilated or cystic duct. You can see how large the duct is by comparing it to other nearby ducts which are more normal in size. There are different portions of this papilloma, some are larger, while others are quite small.

When looking at microscopic images, some pieces of tissue inside the duct do not appear connected to each other. This is because the tissue on the slide is only two dimensional. The actual tissue is three dimensional, and the connections are not visible because they are not included in the plane of section. (This may sound slightly confusing, but look at the next images of this papilloma.)