Invasive breast cancer occurs when a cancerous tumor that started in the breast has spread beyond its original location. Breast cancer is considered invasive when it spreads beyond a breast duct and into the surrounding breast tissue. At that point, it may spread even further, going on to affect a person’s lymph nodes as well as other organs such as the brain or liver. Invasive breast cancer can even spread to an individual’s bones. Once breast cancer has spread from the breast and moved on to other parts of the body, it is referred to as metastatic breast cancer.
Unfortunately, invasive breast cancer is not limited to one type. There are several types that may form in the breast tissue. One type of invasive breast cancer is called invasive ductal carcinoma. This form of cancer initially develops in a milk duct in the breast before going on to affect the fatty part of the breast tissue, and eventually, other parts of the body. This is the most commonly diagnosed type of invasive breast cancer.
Infiltrating lobular carcinoma is also among the types of invasive breast cancer as well. This type develops in a lobule or milk gland and eventually spreads to affect the fatty breast tissue. Eventually, it may spread to other parts of the body as well.
While most breast cancers start in a milk duct or lobule, there are also some types that begin in the connective tissue. This type of body tissue consists of muscle, blood vessels, and fat. When a person develops this type of breast cancer, it is called a sarcoma and can spread to other parts of the body. Cancers that develop in a milk duct or lobule are usually called carcinomas instead.
Breast cancer is typically described in stages. A person who has stage I, II, III, or IV breast cancer has an invasive form of the disease. Stage 0 is not yet invasive but may invade other body tissues if left untreated.
No matter what type of invasive breast cancer a person has, early detection is critical. This is due to the fact that most cancers are more responsive to treatment when they are discovered and treated in an early stage. For this reason, self and doctor-provided breast examinations are typically recommended for women. Mammograms may also be used for early detection of breast cancer in women who are considered at an increased risk.
