If you are suspected of having breast cancer, the doctor performs a biopsy. In a laboratory, this biopsy is examined, and the results will determine if you have breast cancer and what type of cancer it is. The main types are invasive and noninvasive, or "in situ," but beneath these umbrella terms, the National Breast Cancer Foundation lists seven different types of breast cancer.
Invasive Ductal Carcinoma
Invasive ductal carcinoma, or IDC, is the most common type of breast cancer, accounting for between 70 and 80 percent of all breast cancer diagnosis. In IDC, the cancer begins in the milk ducts, then spreads through the duct walls and grows and spreads to breast tissue nearby. According to the Mayo Clinic, it can remain in a local area or spread throughout the body by way of the bloodstream or lymph system.
Invasive Lobular Carcinoma
Invasive lobular carcinoma (ILC) is much less common than IDC. It begins in the part of the breast that produces the milk, rather than in the milk ducts. Like IDC, it can easily spread throughout the body. The American Cancer Society (ACS) reports that ILC is not easily found on a mammogram, and symptoms are usually a fullness or thickening in a particular area of the breast, rather than a specific lump.
Inflammatory Breast Cancer
The National Breast Cancer Foundation (NBCF) reports that inflammatory breast cancer is very rare, accounting for only 1 to 5 percent of all diagnoses. However, it is a very aggressive form, blocking the lymph system of the breasts, causing them to appear swollen and inflamed.
Tubular Carcinoma
Tubular carcinomas are another type of ductal breast cancer, but they are called tubular because of the appearance of the cancer cells when examined under a microscope. Usually found in women age 50 or above, the NBCF states that tubular carcinoma has a 95 percent 10-year survival rate.
Medullary Carcinoma
Medullary carcinoma also gets its name from the appearance of the cells when being examined, as they resemble the gray matter of the medulla portion of the brain. The ACS reports that medullary cancer cells are quite large, so the boundary between cancerous tissues and normal tissues are highly visible. This type of breast cancer is rare and appears most often in women between 40 and 50 years of age.
Mucinous Carcinoma
Mucinous carcinoma is also rare, with only 1 to 2 percent of all breast cancers. What characterizes this breast cancer is that it produces mucous, and, unlike medullary carcinoma, the cells are not clearly defined. However, the NBCF reports that prognosis is good.
Ductal Carcinoma In Situ
Ductal carcinoma in situ is also referred to as DCIS. It is reported by the American Cancer Society as the most common, non-invasive breast cancer. In DCIS, the cancer cells remain in the milk ducts and do not spread to surrounding tissues. However, if the cancer cells appear to be dying when examined, it can mean the tumor will be aggressive.
