Breast cancer is the most common cancer in women and is second only to lung cancer as the leading cause of cancer deaths among women in the World.
There are several different types of breast cancer. Breast tumors may have a single type, a combination, or a mixture of invasive and noninvasive (in situ) cancer.
This is the most common form of breast cancer. Tumors form in the cells of the milk ducts, which carry milk to the nipples. Ductal carcinoma can be invasive with the potential to spread or non-invasive (also called ductal carcinoma in situ or DCIS). About one in five new breast cancer cases are DCIS. The chance for successful treatment of DCIS usually is very high.
Lobular carcinoma is the second most common type of breast cancer. This disease occurs in the lobules, which are the milk-producing glands. Lobular breast cancer can be non-invasive (in situ or LCIS, also called lobular neoplasia) or invasive (have a tendency to spread).About one in 10 breast cancer cases are invasive lobular cancer.
Inflammatory breast cancer
Inflamatory breast cancer, or IBC, is a rare, aggressive form of breast cancer that affects the dermal lymphatic system. Rather than forming a lump, IBC tumors grow in flat sheets that cannot be felt in a breast exam.
Triple-negative breast cancer
Also rare, triple-negative breast cancer is usually an invasive ductal carcinoma with cells that lack estrogen and progesterone receptors and do not have an excess of HER2 protein on their surfaces. These types of breast cancers tend to spread more quickly and do not respond to hormone therapy or drugs that target HER2.
Recurrent breast cancer
This is a cancer that has returned after being undetected for a time. It can occur in the remaining breast tissue or at other sites such as the lungs, liver, bones or brain. Even though these tumors are in new locations, they still are called breast cancer.