Types of Breast Cancers

Breast Tissue

The breast is made up of various types of tissues. These tissues change over a woman's lifetime as her hormones change. Before menopause, a woman's breasts are mostly made of dense, fibrous tissue and fat. As a woman passes through menopause, this fibrous tissue often turns to fat. This causes the breasts to feel much softer and less lumpy. If a woman takes estrogen after menopause, her breasts may often remain fibrous.

Fibrous tissue can sometimes hide a small cancer making it more difficult to feel or find on a mammogram. It is still important to obtain annual mammograms and examine your breast regularly. As you become older with less hormonal influence on your breast tissue, visibility on a mammogram should improve.

There are several types of breast cancers.

Infiltrating Ductal Carcinoma (most common type) is a breast cancer that starts in the milk duct and spreads through the ductal wall into surrounding tissue. Once that invasion has occurred, the cells can enter lymph vessels and blood vessels. These vessels are pathways that can carry cancer cells to other parts of the body. For this reason, breast cancer is often described as a system wide disease.
Ductal Carcinoma in Situ (DCIS) is a non-invasive type of breast cancer. It cannot spread. It is important to surgically remove all traces of the DCIS to improve local control of the cancer.
Infiltrating Lobular Carcinoma is a cancer that starts in the lobule of the breast. It has microscopic projections that can break through the lobule wall and start moving into the surrounding tissue, often making this a more difficult cancer to diagnose at an early stage. It is treated the same as infiltrating ductal carcinoma, although sometimes clear lumpectomy margins are more difficult to obtain. It is also considered a system wide disease.
Inflammatory Breast Cancer is characterized by redness and swelling of the breast with skin changes. This breast cancer can grow very rapidly. It has a higher chance of spreading elsewhere in the body and must be treated more quickly. It is treated first with chemotherapy, followed by surgery and radiation therapy.