Breast cancer happens when cells in your breast grow and divide in an uncontrolled way, creating a mass of tissue called a tumor. Signs of breast cancer can include feeling a lump in your breast, experiencing a change in the size of your breast and seeing changes to the skin on your breasts. Mammograms can help with early detection.
Breast cancer originates in your breast tissue. It occurs when breast cells mutate (change) and grow out of control, creating a mass of tissue (tumor). Like other cancers, breast cancer can invade and grow into the tissue surrounding your breast. It can also travel to other parts of your body and form new tumors. When this happens, it’s called metastasis.
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Breast cancer is one of the most common cancers among women, second only to skin cancer. It’s most likely to affect women over the age of 50.
Though rare, men can also develop breast cancer. Approximately 2,600 men develop male breast cancer every year in the United States, making up less than 1% of all cases.
Transgender women are more likely to develop breast cancer compared to cisgender men. Additionally, transgender men are less likely to develop breast cancer compared to cisgender women.
Breast cancer is most often diagnosed in adults over the age of 50, but it can occur at any age.
Overall, women who are non-Hispanic white have a slightly higher chance of developing breast cancer than women of any other race or ethnicity. Women who are non-Hispanic Black are almost as likely as non-Hispanic white women to develop the disease. Statistically, women who are Asian, Hispanic or Native American are the least likely to develop breast cancer.
In the United States, breast cancer is the second-leading cause of cancer death in women, after lung cancer. It’s also the leading cause of cancer death among women ages 35 to 54.
There are several different types of breast cancer, including:
When we say “breast cancer,” we usually mean cancers that form in milk ducts or lobules. Cancers can also form in other parts of your breast, but these types of cancer are less common. These can include:
Breast cancer symptoms can vary for each person. Possible signs of breast cancer include:
Some people don’t notice any signs of breast cancer at all. That’s why routine mammograms and are so important.
Breast cancer develops when abnormal cells in your breast divide and multiply. But experts don’t know exactly what causes this process to begin in the first place.
However, research indicates that are several risk factors that may increase your chances of developing breast cancer. These include:
There are many other factors that can increase your chances of developing breast cancer. Talk to your healthcare provider to find out if you’re at risk.
Your healthcare provider will perform a breast examination and ask about your family history, medical history and any existing symptoms. Your healthcare provider will also recommend tests to check for breast abnormalities. These tests may include:
If your healthcare provider sees anything suspicious on the imaging tests, they may take a biopsy of your breast tissue. They’ll send the sample to a pathology lab for analysis.
Staging helps describe how much cancer is in your body. It’s determined by several factors, including the size and location of the tumor and whether the cancer has spread to other areas of your body. The basic breast cancer stages are:
There are several breast cancer treatment options, including surgery, chemotherapy, radiation therapy, hormone therapy, immunotherapy and targeted drug therapy. What’s right for you depends on many factors, including the location and size of the tumor, the results of your lab tests and whether the cancer has spread to other parts of your body. Your healthcare provider will tailor your treatment plan according to your unique needs. It’s not uncommon to receive a combination of different treatments, too.
Breast cancer surgery involves removing the cancerous portion of your breast and an area of normal tissue surrounding the tumor. There are different types of surgery depending on your situation, including:
Your healthcare provider may recommend chemotherapy for breast cancer before a lumpectomy in an effort to shrink the tumor. Sometimes, it’s given after surgery to kill any remaining cancer cells and reduce the risk of recurrence (coming back). If the cancer has spread beyond your breast to other parts of your body, then your healthcare provider may recommend chemotherapy as a primary treatment.
Radiation therapy for breast cancer is typically given after a lumpectomy or mastectomy to kill remaining cancer cells. It can also be used to treat individual metastatic tumors that are causing pain or other problems.
Some types of breast cancer use hormones — such as estrogen and progesterone — to grow. In these cases, hormone therapy can either lower estrogen levels or stop estrogen from attaching to breast cancer cells. Most often, healthcare providers use hormone therapy after surgery to reduce the risk of breast cancer recurrence. However, they may also use it before surgery to shrink the tumor or to treat cancer that has spread to other parts of your body.
Immunotherapy uses the power of your own immune system to target and attack breast cancer cells. Treatment is given intravenously (through a vein in your arm or hand). Your healthcare provider might use immunotherapy for breast cancer in combination with chemotherapy.
Some drugs can target specific cell characteristics that cause cancer. Your healthcare provider might recommend targeted drug therapy in cases where breast cancer has spread to other areas of your body. Some of the most common drugs used in breast cancer treatment include monoclonal antibodies (like trastuzumab, pertuzumab and margetuximab), antibody-drug conjugates (like ado-trastuzumab emtansine and fam-trastuzumab deruxtecan) and kinase inhibitors (such as lapatinib, neratinib and tucatinib).
While you can’t prevent breast cancer altogether, there are certain things you can do to reduce your risk of discovering it at an advanced stage. For example:
If you’ve been diagnosed with breast cancer, your healthcare provider will talk with you in detail about your treatment options. Treatment and recovery will be different for everyone, so they can tell you what to expect in your situation.
People with early-stage breast cancer often manage their condition successfully with treatment. In fact, many people who’ve received a breast cancer diagnosis go on to live long, fulfilling lives. Late-stage breast cancer is more difficult to treat, however, and can be fatal.
The overall five-year survival rate for breast cancer is 90%. This means that 90% of people diagnosed with the disease are still alive five years later. The five-year survival rate for breast cancer that has spread to nearby areas is 86%, while the five-year survival rate for metastatic breast cancer is 28%. Fortunately, the survival rates for breast cancer are improving as we learn more about the disease and develop new and better approaches to management.
Keep in mind that survival rates are only estimates. They can’t predict the success of treatment or tell you how long you’ll live. If you have specific questions about breast cancer survival rates, talk to your healthcare provider.
In addition to having routine checkups and mammograms, you should call your healthcare provider if you notice any changes in your breasts.
Learning everything you can about your diagnosis can help you make informed decisions about your health. Here are some questions you may want to ask your healthcare provider:
A note from Cleveland Clinic
Being diagnosed with breast cancer can feel scary, frustrating and even hopeless. If you or a loved one is facing this disease, it’s important to take advantage of the many resources available to you. Talk to your healthcare provider about your treatment options. You may even want to get a second opinion before making a decision. You should feel satisfied and optimistic about your treatment plan. Finally, joining a local support group can help with feelings of isolation and allow you to talk with other people who are going through the same thing.
Last reviewed by a Cleveland Clinic medical professional on 01/21/2022.
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