Breast cancer screenings
Mammogram - breast cancer screening; Breast exam - breast cancer screening; MRI - breast cancer screening
Breast cancer screenings can help find breast cancer early, before you notice any symptoms. In many cases, finding breast cancer early makes it easier to treat or cure. But screenings also have risks, such as missing signs of cancer. When to start screenings may depend on your age and risk factors.
Of all the different types of cancers, breast cancer is one of the most talked about, and with good reason. One out of every eight women will develop breast cancer sometime in their life. That's why every woman should be thinking about how to protect herself from this disease. Breast cancer is cancer that forms in the breast. Usually, it begins in the tubes that transport milk from the breast to the nipple. If the cancer spreads to other parts of the breast or body, it's called invasive breast cancer. Some breast cancers are more aggressive, growing more quickly than others. Although women are 100 times more likely to develop breast cancer, men can also get the disease because they do have breast tissue. You're more likely to get breast cancer if you're over 50, you started your periods before age 12, or you have a close family member with the disease. Drinking more than a couple of glasses of alcohol a day and using hormone replacement therapy for several years also may increase your risk. The telltale sign of breast cancer is a lump in your breast or armpit. You may also notice a change in the shape, size, or texture of your breast, or have fluid coming from your nipple when you're not breastfeeding. If you notice any changes in your breasts, call your doctor. You'll probably need to have an imaging scan, such as a mammogram, MRI, or ultrasound. A piece of tissue may be removed from your breast, called a biopsy. With these tests, your doctor can tell whether you have breast cancer, and if so, determine whether or not it has spread. So, how do we treat breast cancer? That really depends on the type of cancer, and how quickly it's spreading. Your doctor may recommend that you have the cancer removed with surgery. Sometimes it's enough just to remove the lump. That's called a lumpectomy. In other cases, the doctor will need to remove the entire breast to get rid of all the cancer or prevent it from coming back. That's called a mastectomy. Other treatments for breast cancer include chemotherapy, medicines that kill cancer cells, and radiation therapy, which uses energy to destroy cancer. Women whose cancer is fueled by the hormone estrogen may receive hormone therapy to block the effects of estrogen on their cancer. Today's breast cancer treatments are better than ever. Many women who have breast cancer go on to live long, healthy lives. The outlook really depends on how fast the tumor is growing, and how far it has spread. That's why it's so important to report any changes in your breasts to your doctor as soon as you notice them. Women who are at an especially high risk for breast cancer because of their family history can talk to their doctor about taking medicine or even having surgery to reduce their risk.
A mammogram is the most common type of screening. It is an x-ray of the breast using a special machine. This test is done in a hospital or clinic and only takes a few minutes. Mammograms can find tumors that are too small to feel.
Mammography is performed to screen women to detect early breast cancer when it is more likely to be cured. Mammography is generally recommended for:
- Women starting at age 40, repeated every 1 to 2 years. (This is not recommended by all expert organizations.)
- All women starting at age 50, repeated every 1 to 2 years.
- Women with a mother or sister who had breast cancer at a younger age should consider yearly mammograms. They should begin earlier than the age at which their youngest family member was diagnosed.
Mammograms work best at finding breast cancer in women ages 50 to 74. For women younger than age 50, the screening can be helpful, but may miss some cancers. This may be because younger women have denser breast tissue, which makes it harder to spot cancer. It is not clear how well mammograms work at finding cancer in women age 75 and older.
This is an exam to feel the breasts and underarms for lumps or unusual changes. Your health care provider may perform a clinical breast exam (CBE). You can also check your breasts on your own. This is called a breast self-exam (BSE). Doing self-exams may help you become more familiar with your breasts. This may make it easier to notice unusual breast changes.
Keep in mind that breast exams do not reduce the risk of dying from breast cancer. They also do not work as well as mammograms to find cancer. For this reason, you should not rely only on breast exams to screen for cancer.
Not all experts agree about when to have or start having breast exams. In fact, some groups do not recommend them at all. However, this does not mean you should not do or have breast exams. Some women prefer to have exams.
Talk with your provider about the benefits and risks for breast exams and if they are right for you.
If you're a woman, your doctor or gynecologist may have recommended that you examine your breasts every month to check for lumps. You might be wondering, why do I need to do a breast self-exam? Or, you might ask, how do I examine my breasts, and what exactly am I looking for? Well, let's talk about why, and how to examine your breasts. Why examine your breasts? Well, for one thing, it helps you get an idea of how they normally feel. Then if there's ever a problem, you'll be familiar enough with your breasts to spot it. For example, a lump on your breast could be a sign of breast cancer. Finding that lump could allow you to get checked out with a mammogram earlier than you might have done if you didn't do breast self exams. But, this is a two edged sword. Many expert groups no longer recommend routine breast self examination because the consequences of over treatment of benign or normal lumps may outweigh the benefits of early detection. Lumps lead to extra mammograms, which often lead to biopsies, and the biopsies turn out to be benign, or normal, in more than 90% of cases. But, not always. Some expert groups simply recommend breast self awareness. Ultimately, the choice is yours. If you are going to do breast self exam, the best day to do a self exam is about 3 to 5 days after your period ends. Your breasts are naturally less lumpy right after your period, so there's less of a chance that you'll mistake a normal bump for an abnormal growth. If you've already gone through menopause and your periods have stopped, just do your exam on the same day every month. Mark it on your calendar so you won't forget. To do the exam, lie on your back, as it's easier to feel any lumps or changes when you're lying down. First, put your right hand behind your head. Then, using the middle fingers on your left hand, gently but firmly press down, circling your entire breast. Make sure you cover the whole right breast. Squeeze your nipple gently. See if any fluid comes out. Now, sit up, and feel around your armpit. When you're done with the right breast, repeat the whole check on the left side. Next, stand in front of a mirror. With your arms down at your sides, look at both breasts. Check the shape of each breast. Look for any changes in the skin, like dimpling or puckering. Also see if your nipples now turn inward. Now, do the exact same check again with your arms over your head. After you've done a few breast self-exams, you'll become familiar with the look and shape of your breasts. At each exam, you're looking for anything different, like new bumps, changes in the texture of your skin, or discharge from your nipple. If you do notice that something has changed, don't panic, it could mean many different things. But, call your doctor as soon as you can so you can find out what's caused the change, and, if necessary, get it treated.
MRI (Magnetic Resonance Imaging)
An MRI uses powerful magnets and radio waves to find signs of cancer. This screening is done only in women who have a high risk for breast cancer.
Women at high risk for breast cancer (greater than 20% to 25% lifetime risk) should have an MRI along with a mammogram every year. You may have a high risk if you have:
- A family history of breast cancer, most often when your mother or sister had breast cancer at an early age
- Lifetime risk for breast cancer is 20% to 25% or higher
- Certain BRCA mutations, whether you carry this marker or a first degree relative does and you have not been tested
- First degree relatives with certain genetic syndromes (Li-Fraumeni syndrome, Cowden and Bannayan-Riley-Ruvalcaba syndromes)
It is not clear how well MRIs work to find breast cancer. Although MRIs find more breast cancers than mammograms, they are also more likely to show signs of cancer when there is no cancer. This is called a false-positive result. For women who have had cancer in one breast, MRIs can be very helpful for finding hidden tumors in the other breast. You should do a MRI screening if you:
- Are at very high risk for breast cancer (those with a strong family history or genetic markers for breast cancer)
- Have very dense breast tissue
Benefits and Risks of Screenings
When and how often to have a breast screening test is a choice you must make. Different expert groups do not fully agree on the best timing for screening.
Before having a mammogram, talk to your provider about the pros and cons. Ask about:
- Your risk for breast cancer.
- Whether screening decreases your chance of dying from breast cancer.
- Whether there is any harm from breast cancer screening, such as side effects from testing or overtreatment of cancer when it's discovered.
Risks of screenings can include:
- False-positive results. This occurs when a test shows cancer when there is none. This can lead to having more tests that also have risks. It can also cause anxiety. You may be more likely to have a false-positive result if you are younger, have a family history of breast cancer, have had breast biopsies in the past, or take hormones.
- False-negative results. These are tests that come back normal even though there is cancer. Women who have false-negative results do not know they have breast cancer and delay treatment.
- Exposure to radiation is a risk factor for breast cancer. Mammograms expose your breasts to radiation.
- Overtreatment. Mammograms and MRIs may find slow-growing cancers. These are cancers that may not shorten your life. At this time, it is not possible to know which cancers will grow and spread, so when cancer is found it is usually treated. Treatment can cause serious side effects.
Henry NL, Shah PD, Haider I, Freer PE, Jagsi R, Sabel MS. Cancer of the breast. In: Niederhuber JE, Armitage JO, Kastan MB, Doroshow JH, Tepper JE, eds. Abeloff's Clinical Oncology. 6th ed. Philadelphia, PA: Elsevier; 2020:chap 88.
National Cancer Institute website. Breast cancer screening (PDQ) - health professional version.
Siu AL; U.S. Preventive Services Task Force. Screening for breast cancer: U.S. Preventive Services Task Force recommendation statement. Ann Intern Med. 2016;164(4):279-296. PMID: 26757170
Last reviewed on: 7/28/2020
Reviewed by: Todd Gersten, MD, Hematology/Oncology, Florida Cancer Specialists & Research Institute, Wellington, FL. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.