The most common breast cancer is invasive ductal carcinoma (IDC), which accounts for about 80% of invasive breast cancers. IDC begins in a milk passage or duct and then invades the tissue of the breast. It can then spread to other parts of the body.

The most common noninvasive breast cancer is Ductal carcinoma in situ (DCIS). DCIS means the cancer is confined to the ducts and has not spread into the tissue of the breast. Nearly all women with cancer at this stage can be cured.

There are several less common types of breast cancer. Medullary cancer accounts for about 5% of breast cancers. This special type of infiltrating breast cancer has a distinct boundary between tumor tissue and normal tissue. Other special features include large cancer cells and the presence of immune system cells at the edges of the tumor.

Inflammatory breast cancer (IBC) is a rare type of invasive breast cancer that accounts for about 1-3% of all breast cancers. Usually there is no lump or tumor with IBC; instead, the skin of the breast will look red and feel warm, and have a thick, pitted appearance similar to an orange peel. The affected breast may become larger or firmer, tender, or itchy. IBC is often mistaken for infection in its early stages. It has a higher chance of spreading and a worse outlook than typical invasive cancers.

For more information about other types of breast cancer, visit www.cancer.org/breastcancer.

When treating breast cancer, two or more methods are often used in combination. Surgical treatment may mean a lumpectomy, which is surgical removal of the tumor with clear margins, or a mastectomy, which is surgical removal of the breast.

Chemotherapy is the use of cancer-killing drugs that are injected into a vein or taken as a pill. Radiation therapy uses high-energy rays, such as x-rays, to kill or shrink cancer cells. Hormone therapy, such as the drug tamoxifen, is used to block the effect of estrogen or to lower its levels. Targeted therapy is another option that uses drugs, such as trastuzumab, to treat breast cancer.

Getting their annual mammogram is something women can do to save lives. The earliest sign of breast cancer is usually an abnormality detected on a mammogram before it can be felt by a woman or a health care professional. Mammography will detect about 80-90% of breast cancers in women without symptoms.

National Mammography Day is October 19. To help women choose the mammography facility best suited for them, ACS has developed guides that compare services, prices, and other information. Check out the 2007 Indiana Mammography Facility Guide at www.cancer.org/indianamammogram or the 2007 Michigan Mammography Facility Guide at www.cancer.org/michiganmammogram to find a mammography facility in your county.