Also see “carcinoma in situ”. In the normal location. An “in situ” tumor is one that is confined to its site of origin and has not invaded neighboring tissue or gone elsewhere in the body. In breast cancer, the term ductal carcinoma in situ (DCIS) is such an example. The “in situ” phrase means that we can tell for sure that these cells have the POTENTIAL to do their cancer thing (which means, to invade into surrounding tissue and eventually spread elsewhere), but that they have not yet invaded even the tissue right around the DCIS cells. You can think of these cells as “cancer seeds”, which haven’t yet sprouted, but have all the capability of doing so if left in place.

A cut. When making an incision, a surgeon is making a cut.

A biopsy in which only a sample of the suspicious tissue is cut into (incised) and removed for purposes of diagnosis. A incisional biopsy is in contrast to an excisional biopsy in which an entire lesion, usually a tumor, is removed.

Also called ductal carcinoma in situ. See: DCIS.

This term is frequently included as a descriptor of the breast cancer on the pathology report. It is important to know that this term does not carry any extra information other than another way of saying that it is cancer. So it is really kind of redundant. But the term is used to distinguish from the non-invasive cells that are seen sometimes seen, so called “cancer seeds (or intraductal cancer)”, in which case, there has not even been any “sprouting” of the cancer cells into surrounding tissues. Cancer cells which have “sprouted” into the surrounding tissues are called invasive, and this is the case even in the very earliest stages of breast cancer. So don’t think that this term carries any awful prognosis.