MEDICAL ANIMATION TRANSCRIPT: You or someone you care about may have been recently diagnosed with breast cancer. This video will help you understand what breast cancer is and how it affects your body. The breasts are a pair of organs that sit directly under the skin on your chest. On the outside of the breast is the nipple. The darker circle of skin surrounding it is called the areola. In women, breasts are made of fatty tissue, milk producing glands, and tubes called ducts. A large network of lymph vessels and lymph nodes sits in and around the breast. Fluid from the breast drains through the lymph vessels into the lymph nodes. If the fluid contains harmful substances, such as bacteria or viruses, immune cells inside the lymph nodes attack and destroy them. From there, most of the fluid passes to lymph nodes under your arm. Then to other lymph nodes and vessels, emptying into your bloodstream. Most breast cancer starts in the ducts of the breast, but it can grow in any part of the breast. Here, cancer cells form from duct cells lining the ducts. They can grow and multiply to form a cancerous tumor. Over time, the cancer cells can spread through the lymph nodes. The following may be signs or symptoms of breast cancer. Note, that these signs and symptoms are not all inclusive. During a routine breast exam, you or your doctor may feel a small, hard lump in your breast or underarm. In addition, you may have some liquid coming out of your nipple. Or you may see dimples in the skin of your breast. Your doctor will use certain terms to describe the progression of your cancer called staging. Staging for breast cancer is complex. The following staging descriptions are meant as a general overview and are not all inclusive. Stage 0 means abnormal cells are found, but have not spread beyond where they started to other tissues in the breast. Stage 1 means a tumor smaller than two centimeters within the breast tissue. Stage 2A means the breast may have cancer in lymph nodes in the armpit. Or it can be a tumor two centimeters or smaller with cancer in the armpit lymph nodes. Stage 2A can also be a tumor between two centimeter to five centimeters with no spread to the lymph nodes. Stage 2B means the breast may have a tumor between two centimeters to five centimeters with cancer in the armpit lymph nodes. Or it can be a tumor larger than 5 centimeters with no lymph nodes spread. Stage 3A means the breast may have any size tumor with cancer in the armpit lymph nodes. Or it can be a tumor larger than 5 centimeters with cancer in the armpit lymph nodes. Stage 3B means the tumor may be any size and cancer may have spread to the chest wall, the skin of the breast, and/or lymph nodes in the armpit. Stage 3C means the breast may have no visible tumor or any size tumor with spread to the lymph nodes in the armpit, breast bone, or around the collarbone. Stage 4 means the cancer has spread to distant organs. You may be wondering how you got breast cancer. While it's impossible to predict exactly who will get breast cancer, there are some things that can increase your risk: being female, increased age, taking hormone replacement therapy, having your first child after the age of 30, exposure to chest radiation, and a family history of breast cancer. This list is not all inclusive. As you deal with a diagnosis of breast cancer, continue to talk to your doctor and your cancer care team.