Breasts are made of lobules, glands, ducts and fibrous tissue, all of which are made up of cells that have the potential to form tumors. Tumors can either be benign (not cancer) or malignant (cancer). Though the American Cancer Society reports that most breast tumors are not cancerous, more than 192,000 women and about 2,000 men in the U.S. are diagnosed with breast cancer annually, according to the National Cancer Institute. The type of breast tumor enables the patient and doctor to make the most informed decision concerning treatment strategy.
Fibroadenoma
Susan G. Komen for the Cure describes fibroadenomas as solid benign tumors, meaning they are not cancer. Fibroadenomas are more common in younger women and do not increase a woman's risk of developing breast cancer later in life. However, they can be surgically removed if they are large or painful.
Intraductal papillomas
This type of benign breast tumor develops in the breast ducts, according to Susan G. Komen for the Cure. The ducts are the part of the breast that brings milk to the nipple, and the small mass in the duct may cause a nipple discharge to appear. A single intraductal papilloma does not increase a woman's risk of breast cancer, but the appearance of many of these small masses represents a small increase in breast cancer risk.
Sclerosing Lymphocytic Lobulitis
Susan G. Komen for the Cure reports that this type of tumor most often affects women with type-1 diabetes. The tumors begin in the ducts or lobules and are usually hard and small masses. They also do not appear to be linked to an increase in breast cancer.
Ductal Carcinoma
Ductal carcinoma is a type of malignant breast tumor. The National Cancer Institute reports that this type of cancer begins in the cells lining a breast duct. According to the American Cancer Society, it is the most common type of breast cancer, accounting for about 20 percent of all breast cancer cases. If the tumor does not grow beyond the duct, the cancer is called "ductal carcinoma in situ." Sometimes the tumor invades the surrounding breast tissue or spreads to other sites in the body and is called "invasive ductal carcinoma."
Lobular Carcinoma
This is another type of cancerous tumor, beginning in the glands that produce milk, according to the American Cancer Society. Lobular carcinoma in situ means the cancer has not spread beyond the glands, and invasive lobular carcinoma means the cancer has spread to other tissues in the breast or to other sites within the body. Interestingly, the National Cancer Institute reports that lobular carcinoma in situ rarely progresses to invasive lobular carcinoma.
