Common Breast Cancers - Types Of Breast Cancer: Breast Cancer

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Common breast cancers

Ductal carcinoma in situ (DCIS)

A cancer that is contained within the milk-producing gland and is not yet able to spread beyond the immediate area is said to be in situ(see Figure 2). Ductal carcinoma in situ has not invaded the surrounding tissues of the breast, although, if neglected, it might eventually do so. For the time being, however, it doesn't have access to the blood vessels or lymphatic channels that exist in the fatty tissue outside the glands, and so it cannot migrate to other organs in the body.

DCIS is a breast cancer at its earliest stage (Stage 0), still confined to the ducts. Nearly 100% of women with cancer at this stage can be cured. In screening centers, about 20% of the new breast cancers diagnosed are DCIS, and about 80% are invasive.

On a mammogram, DCIS usually looks like a cluster of calcifications (tiny white spots or little grains of sand) without a density (larger spot). About 15% of DCIS patients also have a density, and in 10%, a density is found without calcifications. Occasionally, the doctors find the DCIS on a biopsy specimen without any sign of it appearing on the mammogram.

Invasive (infiltrating) ductal carcinoma (IDC)

This is the most common form of breast cancer; roughly 80% of invasive breast cancers are IDC. This cancer has broken through the duct wall and invaded the surrounding fatty tissue of the breast. From there it can gain access to the blood vessels or lymph channels and spread to other parts of the body.

Invasive (infiltrating) lobular carcinoma

About 10% of invasive breast cancers are this type. The cancer cells have grown through the wall of the lobule and can spread to other parts of the body by way of the lymphatic channels or bloodstream.

Figure 2: Cancer in the breast Normal duct. No cancer cells are present in the normal milk duct in the breast. The lobules of the breast, where milk is produced, are also free of cancer cells. Ductal carcinoma in situ. Breast cancer may begin with the mutation of a single cell in the ducts of a normal breast. When cancer cells begin to multiply rapidly but stay contained inside the duct, the condition is known as ductal carcinoma in situ (DCIS), which often appears as a cluster of white dots or calcifications on a mammogram. Invasive ductal cancer. This type of cancer occurs when cancer cells break through the wall of the duct and enter the surrounding tissues. They may invade the blood vessels and lymph channels of the breast, increasing the likelihood that the cancer will spread (metastasize) to other parts of the body.

Last updated:	April 23, 2007