What to know about multifocal DCIS

The cells remain confined inside the ducts on the tissue examined, but their distribution can affect whether breast-conserving surgery can remove them with a clear rim of healthy tissue.

Pathologists use multifocal when more than one distinct focus of DCIS is identified, often within the same region of a breast. This differs from one continuous area, although imaging cannot always show the exact boundaries between foci.

A mammogram may reveal grouped or separated calcifications, while biopsy confirms the cell type and grade in sampled tissue. The final surgical specimen can provide a fuller map of extent and margin status.

Your team reviews the imaging span, breast size, location of each focus, biopsy grade, hormone-receptor result, and your preferences. Lumpectomy may be considered when all known disease can be removed with acceptable margins and a suitable breast shape. Mastectomy may be discussed when the involved area is too broad for breast conservation or clear margins are difficult to obtain.

Radiotherapy is commonly considered after breast-conserving surgery. Hormone therapy may be offered for hormone-receptor-positive DCIS to reduce the chance of a future breast event; it does not replace surgery for the known area.

Arrange a prompt review if you notice a new breast lump, bloody nipple discharge, nipple or skin pulling, or a new area of breast swelling. These changes require assessment but do not establish whether DCIS has changed.

After biopsy or surgery, seek urgent medical advice for rapidly increasing swelling, heavy bleeding, spreading redness, fever, chest pain, or trouble breathing. Follow the procedure team's instructions because the expected recovery depends on what was done.

Ask how many foci are visible, whether they appear confined to one region, and how their total span was estimated. You can also ask what margin result the surgeon is aiming for, whether further imaging would change the operation, and how receptor status influences treatment after surgery.