A woman has a 12 percent chance of developing invasive breast cancer in the course of her lifetime. The American Cancer Society estimates about 230,480 new cases of invasive and approximately 57,650 new cases of noninvasive breast cancer will be diagnosed in the United States during 2011. The types of breast cancer are categorized by location and characteristics.
Ductal Carcinoma In-situ (DCIS)
This is the most common type of noninvasive breast cancer. As the name implies, the cancerous cells are confined to the lining of the ducts which are responsible for breast milk production. The abnormal cells have not spread through the duct wall into surrounding breast tissue. DCIS is referred to as stage 0 cancer.
Infiltrating Ductal Carcinoma (IDC)
This type of breast cancer accounts for 78 percent of all malignancies. The abnormal cells have invaded to surrounding tissue, including the lymph nodes. These lesions appear as star-like or rounded masses on mammograms. Generally, these stellate lesions of IDC have a poorer prognosis. Stage 2, 3 and 4 breast cancers are IDC.
Medullary Carcinoma
This is a rare subtype of invasive ductal carcinoma. It accounts for 15 percent of all breast cancer types. Though it can occur at any age, medullary carcinoma usually affects women in their late 40s and 50s. This type of cancer gets its name because it resembles the part of the brain called the medulla oblongata.
Infiltrating Lobular Carcinoma (ILC)
This is the second most common type of invasive breast cancer and accounts for about 10 to 15 percent of all cases of breast cancer. It begins in a duct or lobule and spreads to surrounding breast tissue. ILC usually appears as a thickening in the upper outer quadrant of the breast. It usually affects women between the ages of 45 and 56 years of age.
Tubular Carcinoma
This is a rare subtype of invasive ductal carcinoma. It accounts for about 1 to 2 percent of all breast cancer cases. When examined under a microscope, the tubular carcinoma cells have a distinctive tubular structure. The average age of diagnosis is from the mid-40s to the late 60s. Tubular carcinoma has an excellent 10 year survival rate of 95 percent.
Mucinous Carcinoma (Colloid)
This rare form of invasive ductal carcinoma, also called colloid carcinoma, accounts for about 2 to 3 percent of all cases of breast cancer. The mucus is a main part of the tumor and surrounds the breast cancer cells. Mucinous carcinoma generally affects women who have gone through menopause.
Inflammatory Breast Cancer (IBC)
This is a rare, but highly aggressive type of breast cancer. The abnormal cells block the lymph vessels in the skin of the breast. The breast often appears red and swollen or inflamed. IBC accounts for 1 to 5 percent of all cases of breast cancer diagnosed in the United States. It tends to affect younger women, occurs more frequently and at a younger age in African-American women than in Caucasian women and can occur in men, but usually at an older age than in women.
Sources:
What are the key statistics about breast cancer? : American Cancer Society Sept. 4, 2011
http://www.cancer.org/Cancer/BreastCancer/DetailedGuide/breast-cancer-key-statistics
Types of Breast Cancer: National Breast Cancer Foundation, Inc. Sept. 4, 2011
http://www.nationalbreastcancer.org/About-Breast-Cancer/Types.aspx
Breast Cancer/Invasive Lobular Cancer: College of American Pathologists, Sept. 5, 2011
http://www.cap.org/apps/docs/reference/myBiopsy/BreastInvasiveLobularCarcinoma.pdf
Tubular Carcinoma of the Breast: BreastCancer.org, Sept. 5, 2011
http://www.breastcancer.org/symptoms/types/rare_idc/tubular/
Mucinous Carcinoma of the Breast: BreastCancer.org, Sept. 5, 2011
http://www.breastcancer.org/symptoms/types/rare_idc/mucinous/
Inflammatory Breast Cancer: Questions and Answers: National Cancer Institute, Sept. 5, 2011
http://www.cancer.gov/cancertopics/factsheet/Sites-Types/IBC
Reviewed September 6, 2011
by Michele Blacksberg R.N.
Edited by Jody Smith