The most common type of breast cancer is ductal carcinoma, which begins in the cells of the ducts. Cancer that begins in the lobes or lobules is called lobular carcinoma and is more often found in both breasts than are other types of breast cancer. Inflammatory breast cancer is an uncommon type of breast cancer in which the breast is warm, red, and swollen.

The genes in cells carry the hereditary information that is received from a person’s parents. Hereditary breast cancer makes up approximately 5% to 10% of all breast cancer. Some altered genes related to breast cancer are more common in certain ethnic groups.

Different types of treatment are available for patients with breast cancer. Some treatments are standard (the currently used treatment), and some are being tested in clinical trials. Before starting treatment, patients may want to think about taking part in a clinical trial. A treatment clinical trial is a research study meant to help improve current treatments or obtain information on new treatments for patients with cancer. When clinical trials show that a new treatment is better than the standard treatment, the new treatment may become the standard treatment.

Most patients with breast cancer have surgery to remove the cancer from the breast. Some of the lymph nodes under the arm are usually taken out and looked at under a microscope to see if they contain cancer cells.

Even if the doctor removes all of the cancer that can be seen at the time of surgery, the patient may be given radiation therapy, chemotherapy, or hormone therapy after surgery to try to kill any cancer cells that may be left. Treatment given after surgery to increase the chances of a cure is called adjuvant therapy.

If a patient is going to have a mastectomy, breast reconstruction (surgery to rebuild a breast’s shape after a mastectomy) may be considered. Breast reconstruction may be done at the time of the mastectomy or at a future time. The reconstructed breast may be made with the patient’s own (nonbreast) tissue or by using implants filled with saline or silicone gel. The Food and Drug Administration (FDA) has decided that breast implants filled with silicone gel may be used only in clinical trials. Before the decision to get an implant is made, patients can call the FDA’s Center for Devices and Radiologic Health at 1-888-INFO-FDA (1-888-463-6332) for more information.