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National Spotlight

Financial Resources —Did you know that there are many financial resources that can help people living with breast cancer? Find out more

What is Breast Cancer?

Breast cancer is the most common cancer among women worldwide and the second-most common cancer overall. In 2016, an estimated 246,660 cases of invasive breast cancer will be diagnosed in the U.S. alone. So no matter who you are or where you live, understanding breast cancer is important. But the most important thing to know is this: a diagnosis is not a death sentence. Breast cancer can be treated. 

What is breast cancer?
In a healthy body, natural systems control the creation, growth and death of cells. But when these systems malfunction, more cell growth than death can occur. The result is a mass of tissue we call a malignant tumor—or cancer. And when this process takes place in the breast, it’s breast cancer. Tumors in the breast tend to grow slowly; by the time a lump is large enough to feel, it may have been growing for as long as 10 years. Some tumors, however, are aggressive and grow much faster. 

Non-invasive Breast Cancer
Non-invasive breast cancer (also known as ductal carcinoma in situ or DCIS) occurs when abnormal cells grow inside the milk ducts but have not spread to nearby tissue or beyond. This may also be referred to as “pre-invasive breast carcinoma.” Although the abnormal cells have not spread to tissues outside the ducts, they can develop into invasive breast cancer. LEARN MORE

Invasive Breast Cancer
Invasive breast cancer is when abnormal cells break out of the milk ducts or lobules and move into nearby breast tissue. Cancer cells can travel from the breast to other parts of the body through the blood stream or the lymphatic system. And they may travel early in the process when the tumor is small or later when the tumor is large. 

The lymph nodes in the underarm area (the axillary lymph nodes) are the first place that breast cancer is likely to spread. In advanced stages, breast cancer cells may spread to other parts of the body like the liver, lungs, bones and brain (in a process called metastasis). There, the breast cancer cells may again begin to divide too quickly and form new tumors. LEARN MORE

Stage IV Breast Cancer
Stage IV breast cancer (also known as metastatic or advanced breast cancer) has spread beyond the breast to other parts of the body, most often the bones, lungs, liver or brain. Some women have stage IV when they are first diagnosed but this is not common in the United States. More commonly, metastatic breast cancer arises months or years after a person has completed treatment for early or locally advanced breast cancer (stage I, II, or III.) LEARN MORE

Other Forms of Breast Cancer 
Though they are not specific types of tumors, there are some special forms of breast cancer. These include inflammatory breast cancer (IBC), Paget disease of the breast or nipple, and metaplastic breast cancer. LEARN MORE