Diagnosing DCIS

Ductal carcinoma in situ means abnormal cells are contained within a breast milk duct on the sampled tissue. Imaging locates the area and estimates its extent; the pathology report supplies the definitive microscopic finding.

DCIS may appear on a mammogram as a pattern of tiny calcium deposits called calcifications. Calcifications can also be benign, so their appearance guides whether extra mammogram views or a biopsy are appropriate rather than proving cancer by themselves.

During a core biopsy, samples are taken from the image-guided target. A pathologist checks whether DCIS is present, assesses its grade and may test hormone receptors. Because a needle samples part of an area, surgery can occasionally reveal additional findings that were not in the biopsy cores.

Attend recommended diagnostic imaging and bring earlier breast images if they were obtained elsewhere; comparison can help the radiologist interpret a change. Before biopsy, tell the team about blood-thinning medicines, allergies and any chance of pregnancy, and follow their medicine instructions.

Once pathology is available, review the diagnosis with the breast team. Ask about the location and span seen on imaging, whether the imaging and biopsy results agree, and whether more sampling is needed before treatment planning.

Contact the biopsy service for bleeding that does not stop with firm pressure, rapidly increasing breast swelling, fever, spreading redness, drainage or pain that is worsening instead of settling. Separately, arrange clinical assessment for a new breast lump, bloody nipple discharge, nipple inversion or skin dimpling; these changes need evaluation but do not identify the cause on their own.

Ask whether the report shows DCIS alone or another finding, what the grade and hormone-receptor result mean, and whether the targeted calcifications were present in the sample. For treatment planning, ask how the estimated extent affects the surgical choices and whether further imaging is recommended.