Is the Breast Cancer Invasive?

The single most important fact about any breast cancer is whether it has grown beyond the milk ducts or lobules of the breast where it first started.

Normal Cells

normal cells

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Non-invasive Cells

non-invasive cancer

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Non-invasive cancers stay within the milk ducts or milk lobules in the breast. They do not grow into or invade normal tissues within or beyond the breast. These are sometimes called in situ or pre-cancers.

Invasive Cells

invasive

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If the cancer has grown beyond where it started, it is called invasive. Most cancers are invasive. Sometimes cancer cells can also spread to other parts of the body through the blood or lymph system.

You may see these descriptions of cancer in your report

DCIS (Ductal Carcinoma In Situ)

This is a cancer that is not invasive. It stays inside the milk ducts.

LCIS (Lobular Carcinoma In Situ)

This is a tumor that is an overgrowth of cells that stay inside the milk-making part of the breast (called lobules). LCIS is not a true cancer. It is a warning sign for an increased risk of having an invasive cancer in the future, in either breast.

IDC (Invasive Ductal Carcinoma)

This is a cancer that begins in the milk duct but grows into the surrounding normal tissue inside the breast. This is the most common kind of breast cancer.

ILC (Invasive Lobular Carcinoma)

This is a cancer that starts inside the milk-making glands (called lobules), but grows into the surrounding normal tissue inside the breast.