Staging

Staging is a measure that doctors use to describe how much cancer there is in the body and where it is. Staging usually goes from Stage 1 to Stage 4. DCIS is a Stage 0 because it is a pre-cancer or very-early-stage cancer. Doctors do not routinely perform other tests to find distant spread of cancer for patients who have DCIS, because a diagnosis of DCIS means it has not invaded other tissue.