1. What is a mammogram?

A mammogram is an x-ray of the breast.

Mammograms can be used to check for breast cancer in women who have no signs or symptoms of the disease. This type of mammogram is called a screening mammogram.
Screening mammograms usually involve two x-rays of each breast. They make it possible to detect tumors that cannot be felt. Screening mammograms can also find microcalcifications (tiny deposits of calcium) that sometimes indicate the presence of breast cancer.

Mammograms can also be used to check for breast cancer after a lump or other sign or symptom of breast cancer has been found. This type of mammogram is called a diagnostic mammogram. Signs of breast cancer may include pain, skin thickening, nipple discharge, or a change in breast size or shape. A diagnostic mammogram also may be used to evaluate changes found during a screening mammogram, or to view breast tissue when it is difficult to obtain a screening mammogram because of special circumstances, such as the presence of breast implants (see Question 14).

2. How are screening and diagnostic mammograms different?

Diagnostic mammograms take longer than screening mammograms because they involve more x-rays in order to obtain views of the breast from several angles. The technician may magnify a suspicious area to produce a detailed picture that can help the doctor make an accurate diagnosis.

3. When does the National Cancer Institute (NCI) recommend that women have screening mammograms?



• Women age 40 and older should have mammograms every 1 to 2 years.
• Women who are at higher than average risk of breast cancer should talk with their health care providers about whether to have mammograms before age 40 and how often to have them.

4. What are the factors that place a woman at increased risk of breast cancer?

The risk of breast cancer increases gradually as a woman gets older. However, the risk of developing breast cancer is not the same for all women. Research has shown that the following factors increase a woman’s chance of developing this disease:

• Personal history of breast cancer—Women who have had breast cancer are more likely to develop a second breast cancer.
• Family history—A woman’s chance of developing breast cancer increases if her mother, sister, and/or daughter have been diagnosed with the disease, especially if they were diagnosed before age 50. Having a close male blood relative with breast cancer also increases a woman's risk of developing the disease.

• Certain breast changes found on biopsy—Looking at breast tissue under a microscope allows doctors to determine whether cancer or another type of breast change is present. Most breast changes are not cancer, but some may increase the risk of developing breast cancer. Changes associated with an increased risk of breast cancer include atypical hyperplasia (a noncancerous condition in which cells have abnormal features and are increased in number), lobular carcinoma in situ (LCIS) (abnormal cells are found in the lobules of the breast), and ductal carcinoma in situ (DCIS) (abnormal cells are found in the lining of breast ducts). Because some cases of DCIS will eventually develop into invasive breast cancer, this type of change is actively treated (see Question 10). Women with atypical hyperplasia and LCIS are usually monitored carefully and not actively treated. In addition, women who have had two or more breast biopsies for other noncancerous conditions also have an increased risk of developing breast cancer. This increased risk is due to the conditions that led to the biopsies and not to the biopsy procedure itself.

• Genetic alterations (changes)—Changes in certain genes (for example, BRCA1, BRCA2, and others) increase the risk of breast cancer. These changes are rare; they are estimated to account for no more than 10 percent of all breast cancers.

• Reproductive and menstrual history—Women who began having menstrual periods before age 12 or went through menopause after age 55 are at increased risk of developing breast cancer. Women who have their first child after age 30 or who never have a child are also at increased risk of developing breast cancer.

• Long-term use of menopausal hormone therapy—Women who use combination estrogen-progestin menopausal hormone therapy for more than 5 years have an increased chance of developing breast cancer.

• Breast density —Breast density refers to the relative amounts of different tissue in the breast as seen on a mammogram. Dense breasts have more glandular (milk-producing) and connective tissue than fatty tissue. Low-density breasts have a greater proportion of fatty tissue. Younger women usually have denser breasts than older women. As a woman ages, the amount of glandular tissue normally decreases and the amount of fatty tissue increases. Because breast cancers tend to develop in the dense tissue of the breast, older women whose mammograms show more dense tissue have a higher risk of developing breast cancer. Abnormalities in dense breasts can be more difficult to detect on a mammogram.

• Radiation therapy—Women who had radiation therapy to the chest (including the breasts) before age 30 have an increased risk of developing breast cancer throughout their lives. This includes women treated for Hodgkin lymphoma. Studies show that the younger a woman was when she received her treatment, the higher her risk of developing breast cancer later in life.

• DES (diethylstilbestrol)—The drug DES was given to some pregnant women in the United States between 1940 and 1971. (It is no longer given to pregnant women.) Women who took DES during pregnancy may have a slightly increased risk of breast cancer. The possible effects on their daughters and granddaughters are under study.

• Body weight—Studies have found that the chance of getting breast cancer after menopause is higher in women who are overweight or obese.
• Physical activity level—Women who are physically inactive throughout life may have an increased risk of breast cancer. Being active may help reduce risk by preventing weight gain and obesity.
• Alcohol—Studies indicate that the more alcohol a woman drinks, the greater her risk of breast cancer.

5. What are the chances that a woman in the United States might develop breast cancer?

Age is the most important risk factor for breast cancer. The older a woman is, the greater her chance of developing breast cancer. Most breast cancers occur in women over the age of 50. The number of cases is especially high for women over age 60. Breast cancer is relatively uncommon in women under age 40. The NCI fact sheet Probability of Breast Cancer in American Women provides more information about lifetime risk. This fact sheet is available at http://www.cancer.gov/cancertopics/factsheet/Detection/probability-breast-cancer on the Internet.

6. What is the best method of detecting breast cancer as early as possible?

Getting a high-quality screening mammogram and having a clinical breast exam (an exam done by a health care provider) on a regular basis are the most effective ways to detect breast cancer early. As with any screening test, screening mammograms have both benefits and limitations. For example, some cancers cannot be detected by a screening mammogram but may be found by a clinical breast exam.

Checking one’s own breasts for lumps or other unusual changes is called a breast self-exam, or BSE. Breast self-exams cannot replace regular screening mammograms or clinical breast exams. In clinical trials (research studies), breast self-exams alone have not been found to help reduce the number of deaths from breast cancer.

If a woman chooses to do breast self-exams, it is important to remember that breast changes can occur because of pregnancy, aging, menopause, during menstrual cycles, or taking birth control pills or other hormones. It is normal for breasts to feel a little lumpy and uneven. Also, it is common for breasts to be swollen and tender right before or during a menstrual period. If a woman notices any unusual changes in her breasts, she should contact her health care provider.

7. What are the benefits of screening mammograms?

Several large studies conducted around the world show that breast cancer screening with mammograms reduces the number of deaths from breast cancer for women ages 40 to 69, especially for those over age 50. Studies conducted to date have not shown a benefit from regular screening mammograms, or from a baseline screening mammogram (a mammogram used for comparison), in women under age 40.

8. What are some of the limitations or harms of screening mammograms?

• Finding cancer does not always mean saving lives—Even though mammograms can detect tumors that cannot be felt, finding a small tumor does not always mean that a woman’s life will be saved. Screening mammograms may not help a woman with a fast-growing or aggressive cancer that has already spread to other parts of her body before being detected.

• False negatives—False negatives occur when mammograms appear normal even though breast cancer is present. Overall, screening mammograms miss up to 20 percent of the breast cancers that are present at the time of screening. False negatives occur more often in younger women than in older women because the dense breasts of younger women make breast cancers more difficult to detect in mammograms. As women age, their breasts usually become more fatty (therefore, less dense), and breast cancers become easier to detect with screening mammograms.

• False positives—False positives occur when radiologists decide mammograms are abnormal, but no cancer is actually present. All abnormal mammograms should be followed up with additional testing (a diagnostic mammogram, ultrasound, and/or biopsy) to determine if cancer is present. False positives are more common in younger women, women who have had previous breast biopsies, women with a family history of breast cancer, and women who are taking estrogen (for example, hormone replacement therapy).

• Radiation exposure—Mammograms (as well as dental x-rays and other routine x-rays) use very small doses of radiation. The risk of any harm is very slight, but repeated x-rays could cause problems. The benefits nearly always outweigh the risk. Women should talk with their health care provider about the need for each x-ray. They should also ask about shielding to protect parts of the body that are not in the picture. In addition, they should always let their health care provider and the technician know if there is any possibility that they are pregnant.

9. What is the Breast Imaging Reporting and Database System (BI-RADS®)?

The American College of Radiology (ACR) has established a uniform way for radiologists to describe mammogram findings. The system, called BI-RADS, includes seven standardized categories, or levels. Each BI-RADS category has a follow-up plan associated with it to help radiologists and other physicians appropriately manage a patient’s care.

Breast Imaging Reporting and Database System (BI-RADS)
Category	Assessment	Follow-up
0	Need additional imaging evaluation	Additional imaging needed before a category can be assigned
1	Negative	Continue annual screening mammograms (for women over age 40)
2	Benign (noncancerous) finding	Continue annual screening mammograms (for women over age 40)
3	Probably benign	Receive a 6-month follow-up mammogram
4	Suspicious abnormality	May require biopsy
5	Highly suggestive of malignancy (cancer)	Requires biopsy
6	Known biopsy-proven malignancy (cancer)	Biopsy confirms presence of cancer before treatment begins

Additional information about BI-RADS is available on the ACR Web site at http://www.acr.org or by calling the ACR at 1–800–ACR–LINE (1–800–227–5463).

10. What happens if a mammogram leads to the detection of ductal carcinoma in situ (DCIS)?

Over the past 30 years, improvements in mammography have made it possible to detect a larger number of tissue abnormalities, including DCIS. DCIS is a condition in which abnormal cells are confined to the milk ducts of the breast. The cells have not invaded the surrounding breast tissue. DCIS usually does not cause a lump, so it cannot be detected during a clinical breast exam or BSE. However, mammography is able to detect 80 percent of DCIS cases. Some of these cases will eventually develop into invasive breast cancer.

It is not possible to predict which cases of DCIS will progress to invasive cancer. Therefore, DCIS usually is removed surgically. In the past, DCIS was often treated with a mastectomy, but breast-conserving therapy (breast-sparing surgery plus radiation therapy) is now standard practice for many women with DCIS. Tamoxifen may also be used. Women who have been diagnosed with DCIS should talk with their doctor to make an informed decision about treatment.

11. How much does a mammogram cost?

The cost of screening mammograms varies by state and by facility, and can depend on insurance coverage. However, most states have laws requiring health insurance companies to reimburse all or part of the cost of screening mammograms. Women are encouraged to contact their mammogram facility or their health insurance company for information about cost and coverage.

All women age 40 and older with Medicare can get a screening mammogram each year. Medicare will also pay for one baseline mammogram for a woman between the ages of 35 and 39. There is no deductible requirement for this benefit, but Medicare beneficiaries have to pay 20 percent of the Medicare-approved amount. Information about Medicare coverage is available at http://www.medicare.gov on the Internet, or through the Medicare Hotline at 1–800–MEDICARE (1–800–633–4227). For the hearing impaired, the telephone number is 1–877–486–2048.

12. How can women who are low-income or uninsured obtain a screening mammogram?

Some state and local health programs and employers provide mammograms free or at low cost. For example, the Centers for Disease Control and Prevention (CDC) coordinates the National Breast and Cervical Cancer Early Detection Program. This program provides screening services, including clinical breast exams and mammograms, to low-income, uninsured women throughout the United States and in several U.S. territories. Contact information for local programs is available on the CDC’s Web site at http://apps.nccd.cdc.gov/cancercontacts/nbccedp/contacts.asp or by calling the CDC at 1–800–CDC–INFO (1–800–232–4636).

Information about low-cost or free mammography screening programs is also available through NCI’s Cancer Information Service (CIS) at 1–800–4–CANCER (1–800–422–6237). Women can also check with their local hospital, health department, women’s center, or other community groups to find out how to access low-cost or free mammograms.

13. Where can women get high-quality mammograms?

Women can get high-quality mammograms in breast clinics, hospital radiology departments, mobile vans, private radiology offices, and doctors’ offices.

The Mammography Quality Standards Act (MQSA) is a Federal law designed to ensure that mammograms are safe and reliable. Through the MQSA, all mammography facilities in the United States must meet stringent quality standards, be accredited by the Food and Drug Administration (FDA), and be inspected annually. The FDA ensures that mammography facilities across the country meet MQSA standards. These standards apply to the following people at the mammography facility:

• The technologist who takes the mammogram.
• The radiologist who interprets the mammogram.
• The medical physicist who tests the mammography equipment.

Women can ask their doctors or staff at the mammography facility about FDA certification before making an appointment. All mammography facilities are required to display their FDA certificate. Women should look for the MQSA certificate at the mammography facility and check its expiration date. MQSA regulations also require mammography facilities to give patients an easy-to-read report on the results of their mammogram.

Information about local FDA-certified mammography facilities is available through the CIS at 1–800–4–CANCER (1–800–422–6237). Also, a list of these facilities is on the FDA’s Web site at http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfMQSA/mqsa.cfm on the Internet.

14. What should women with breast implants do about screening mammograms?

Women with breast implants should continue to have mammograms. (A woman who had an implant following breast cancer surgery should ask her doctor whether a mammogram of the reconstructed breast is necessary.) It is important to inform the mammography facility about breast implants when scheduling a mammogram. The technician and radiologist must be experienced in x-raying patients with breast implants. Implants can hide some breast tissue, making it more difficult for the radiologist to detect an abnormality on the mammogram. If the technician performing the procedure is aware a woman has breast implants, steps can be taken to make sure that as much breast tissue as possible can be seen on the mammogram.

15. What is digital mammography? How is it different from conventional (film) mammography?

Both digital and conventional mammography use x-rays to produce an image of the breast; however, conventional mammography stores the image directly on film, whereas digital mammography takes an electronic image of the breast and stores it directly in a computer. This allows the recorded information to be enhanced, magnified, or manipulated for further evaluation. The difference between conventional mammography and digital mammography is like the difference between a traditional film camera and a digital camera. Aside from the difference in how the image is recorded and stored, there is no other difference between the two.

Because digital mammography allows a radiologist to electronically adjust, store, and retrieve digital images, digital mammography may offer the following advantages over conventional mammography:

• Health care providers can share image files electronically, making long-distance consultations with other mammography specialists easier.
• Subtle differences between normal and abnormal tissues may be more easily noted.
• The number of follow-up procedures needed may be fewer.
• Fewer repeat images may be needed, reducing the exposure to radiation.

In January 2000, the FDA approved the use of digital mammography in the United States. In September 2005, preliminary results from a large clinical trial that compared digital mammography to film mammography were published (1). These findings showed no difference between digital and film mammograms in detecting breast cancer in the general population of women in the trial. However, the researchers concluded that women with dense breasts who are premenopausal or perimenopausal (women who had their last menstrual period within 12 months of their mammograms) or who are younger than age 50 may benefit from having a digital rather than a film mammogram.

Some health care providers recommend that women who have a very high risk of breast cancer, such as those with BRCA1 or BRCA2 gene alterations, have digital mammograms instead of conventional mammograms; however, studies showing that digital mammograms are superior to conventional mammograms for these women are lacking.

Digital mammography can be done only in facilities that are certified to practice conventional mammography and have received FDA approval to offer digital mammography. The procedure for having a mammogram with a digital system is the same as with conventional mammography.

16. What other technologies are being developed for breast cancer screening?

NCI is supporting the development of several new technologies to detect breast tumors. This research ranges from methods being developed in research labs to those that have reached clinical trials. Efforts to improve conventional mammography include digital mammography (see Question 15), magnetic resonance imaging (MRI), and positron emission tomography (PET scanning).

In addition to imaging technologies, NCI-supported scientists are exploring methods to detect markers (genetic traits) of breast cancer in blood, urine, or nipple aspirates (fluid from the breast) that may serve as early warning signals for breast cancer. The NCI fact sheet Improving Methods for Breast Cancer Detection and Diagnosis provides more information about technologies that are under development for breast cancer screening and diagnosis. This fact sheet is available at http://www.cancer.gov/cancertopics/factsheet/Detection/breast-cancer on the Internet.

17. How is NCI supporting efforts to find better ways to prevent and treat breast cancer?

NCI conducts and supports ongoing breast cancer research that ranges from basic science through the full spectrum of clinical care.

• Basic research—Researchers are trying to identify the causes of breast cancer, including the role of gene changes or variations in addition to changes in BRCA1 and BRCA2. Scientists are also investigating how hormonal, dietary, and environmental factors might contribute to the development of breast cancer.

• Prevention—As a result of NCI-supported research, the drugs tamoxifen and raloxifene have been approved by the FDA to reduce the risk of developing breast cancer in women who are at high risk for the disease; tamoxifen can be used by both premenopausal and postmenopausal women, whereas raloxifene is appropriate for postmenopausal women only. Currently, researchers are looking for additional ways to prevent breast cancer in women who are at increased risk. They are studying other preventive agents and how changes in diet, physical activity, nutrition, and environmental factors may lead to a reduced risk of developing breast cancer.

• Early detection and diagnosis—Several studies are seeking better ways to detect and diagnose breast cancer, so women can receive treatment sooner.

• Treatment—Numerous studies are being conducted to find more effective and less toxic treatments for breast cancer, better ways to deal with the symptoms of this disease and the side effects of its treatment, and new approaches to improve the quality of life of breast cancer patients and survivors.

In the HTML version of this fact sheet on NCI's Web site (http://www.cancer.gov/cancertopics/factsheet/Detection/mammograms), the text below links to searches of clinical trials or female breast cancer prevention, screening, and treatment. The trials are included in the clinical trials database that can be searched at http://www.cancer.gov/clinicaltrials/search on the Internet.


Current NCI-supported clinical trials for female breast cancer prevention ¹
Current NCI-supported clinical trials for female breast cancer screening ²
Current NCI-supported clinical trials for female breast cancer treatment ³

Additional information about clinical trials is available from NCI's Cancer Information Service (1-800-4-CANCER) or on the main clinical trials page of NCI's Web site at http://www.cancer.gov/clinicaltrials on the Internet.

Selected Reference

1. Pisano ED, Gatsonis C, Hendrick E, et al. Diagnostic performance of digital versus film mammography for breast cancer screening. New England Journal of Medicine 2005; 353(17):1773–1783.

Related NCI materials and Web pages:

• National Cancer Institute Fact Sheet 5.6, Probability of Breast Cancer in American Women ⁴
  (http://www.cancer.gov/cancertopics/factsheet/Detection/probability-breast-cancer)
• National Cancer Institute Fact Sheet 5.14, Improving Methods for Breast Cancer Detection and Diagnosis ⁵
  (http://www.cancer.gov/cancertopics/factsheet/Detection/breast-cancer)
• Breast Cancer Home Page ⁶
  (http://www.cancer.gov/cancertopics/types/breast)
• What You Need To Know About™ Breast Cancer ⁷
  (http://www.cancer.gov/cancertopics/wyntk/breast)

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Glossary Terms

Not normal. An abnormal lesion or growth may be cancer, premalignant (likely to become cancer), or benign (not cancer).

A quickly growing cancer.

A chemical substance found in beer, wine, and liquor. Alcohol is also found in some medicines, mouthwashes, essential oils (scented liquid taken from plants), and household products.

In healthcare, a process used to learn about a patient’s condition. This may include a complete medical history, medical tests, a physical exam, a test of learning skills, tests to find out if the patient is able to carry out the tasks of daily living, a mental health evaluation, and a review of social support and community resources available to the patient.

A benign (not cancer) condition in which cells look abnormal under a microscope and are increased in number.

An initial measurement that is taken at an early time point to represent a beginning condition, and is used for comparison over time to look for changes. For example, the size of a tumor will be measured before treatment (baseline) and then afterwards to see if the treatment had an effect.

Not cancerous. Benign tumors may grow larger but do not spread to other parts of the body. Also called nonmalignant.

A method used by radiologists to interpret and report in a standardized manner the results of mammography, ultrasound, and MRI used in breast cancer screening and diagnosis. Also called Breast Imaging Reporting and Data System.

The removal of cells or tissues for examination by a pathologist. The pathologist may study the tissue under a microscope or perform other tests on the cells or tissue. There are many different types of biopsy procedures. The most common types include: (1) incisional biopsy, in which only a sample of tissue is removed; (2) excisional biopsy, in which an entire lump or suspicious area is removed; and (3) needle biopsy, in which a sample of tissue or fluid is removed with a needle. When a wide needle is used, the procedure is called a core biopsy. When a thin needle is used, the procedure is called a fine-needle aspiration biopsy.

A tissue with red blood cells, white blood cells, platelets, and other substances suspended in fluid called plasma. Blood takes oxygen and nutrients to the tissues, and carries away wastes.

A gene on chromosome 17 that normally helps to suppress cell growth. A person who inherits certain mutations (changes) in a BRCA1 gene has a higher risk of getting breast, ovarian, prostate, and other types of cancer.

A gene on chromosome 13 that normally helps to suppress cell growth. A person who inherits certain mutations (changes) in a BRCA2 gene has a higher risk of getting breast, ovarian, prostate, and other types of cancer.

Glandular organ located on the chest. The breast is made up of connective tissue, fat, and breast tissue that contains the glands that can make milk. Also called mammary gland.

Cancer that forms in tissues of the breast, usually the ducts (tubes that carry milk to the nipple) and lobules (glands that make milk). It occurs in both men and women, although male breast cancer is rare.

Describes the relative amount of different tissues present in the breast. A dense breast has less fat than glandular and connective tissue. Mammogram films of breasts with higher density are harder to read and interpret than those of less dense breasts.

A silicone gel-filled or saline-filled sac placed under the chest muscle to restore breast shape.

An exam by a woman of her breasts to check for lumps or other changes.

A mineral needed for healthy teeth, bones, and other body tissues. It is the most common mineral in the body. A deposit of calcium in body tissues, such as breast tissue, may be a sign of disease.

A term for diseases in which abnormal cells divide without control and can invade nearby tissues. Cancer cells can also spread to other parts of the body through the blood and lymph systems. There are several main types of cancer. Carcinoma is a cancer that begins in the skin or in tissues that line or cover internal organs. Sarcoma is a cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue. Leukemia is a cancer that starts in blood-forming tissue such as the bone marrow, and causes large numbers of abnormal blood cells to be produced and enter the blood. Lymphoma and multiple myeloma are cancers that begin in the cells of the immune system. Central nervous system cancers are cancers that begin in the tissues of the brain and spinal cord. Also called malignancy.

The Cancer Information Service is the National Cancer Institute's link to the public, interpreting and explaining research findings in a clear and understandable manner, and providing personalized responses to specific questions about cancer. Access the CIS by calling 1-800-4-CANCER (1-800-422-6237), or by using the LiveHelp instant-messaging service at https://cissecure.nci.nih.gov/livehelp/welcome.asp. Also called CIS.

The individual unit that makes up the tissues of the body. All living things are made up of one or more cells.

Cancer that forms in tissues of the cervix (the organ connecting the uterus and vagina). It is usually a slow-growing cancer that may not have symptoms but can be found with regular Pap tests (a procedure in which cells are scraped from the cervix and looked at under a microscope). Cervical cancer is almost always caused by human papillomavirus (HPV) infection.

Having to do with the examination and treatment of patients.

A physical exam of the breast performed by a health care provider to check for lumps or other changes. Also called CBE.

A type of research study that tests how well new medical approaches work in people. These studies test new methods of screening, prevention, diagnosis, or treatment of a disease. Also called clinical study.

Supporting tissue that surrounds other tissues and organs. Specialized connective tissue includes bone, cartilage, blood, and fat.

The process of identifying a disease, such as cancer, from its signs and symptoms.

X-ray of the breasts used to check for breast cancer after a lump or other sign or symptom of breast cancer has been found.

The things a person eats and drinks.

A synthetic form of the hormone estrogen that was prescribed to pregnant women between about 1940 and 1971 because it was thought to prevent miscarriages. Diethylstilbestrol may increase the risk of uterine, ovarian, or breast cancer in women who took it. It also has been linked to an increased risk of clear cell carcinoma of the vagina or cervix in daughters exposed to diethylstilbestrol before birth. Also called DES.

The use of a computer, rather than x-ray film, to create a picture of the breast.

The amount of medicine taken, or radiation given, at one time.

Any substance, other than food, that is used to prevent, diagnose, treat or relieve symptoms of a disease or abnormal condition. Also refers to a substance that alters mood or body function, or that can be habit-forming or addictive, especially a narcotic.

In medicine, a tube or vessel of the body through which fluids pass.

The most common type of breast cancer. It begins in the cells that line the milk ducts in the breast.

A type of hormone made by the body that helps develop and maintain female sex characteristics and the growth of long bones. Estrogens can also be made in the laboratory. They may be used as a type of birth control and to treat symptoms of menopause, menstrual disorders, osteoporosis, and other conditions.

A record of the relationships among family members along with their medical histories. This includes current and past illnesses. A family history may show a pattern of certain diseases in a family. Also called family medical history.

The use of x-rays to create a picture of the breast on a film.

Monitoring a person's health over time after treatment. This includes keeping track of the health of people who participate in a clinical study or clinical trial for a period of time, both during the study and after the study ends.

An agency in the U.S. federal government whose mission is to protect public health by making sure that food, cosmetics, and nutritional supplements are safe to use and truthfully labeled. The Food and Drug Administration also makes sure that drugs, medical devices, and equipment are safe and effective, and that blood for transfusions and transplant tissue are safe. Also called FDA.

The functional and physical unit of heredity passed from parent to offspring. Genes are pieces of DNA, and most genes contain the information for making a specific protein.

Inherited; having to do with information that is passed from parents to offspring through genes in sperm and egg cells.

An organ that makes one or more substances, such as hormones, digestive juices, sweat, tears, saliva, or milk. Endocrine glands release the substances directly into the bloodstream. Exocrine glands release the substances into a duct or opening to the inside or outside of the body.

A cancer of the immune system that is marked by the presence of a type of cell called the Reed-Sternberg cell. The two major types of Hodgkin lymphoma are classical Hodgkin lymphoma and nodular lymphocyte-predominant Hodgkin lymphoma. Symptoms include the painless enlargement of lymph nodes, spleen, or other immune tissue. Other symptoms include fever, weight loss, fatigue, or night sweats. Also called Hodgkin disease.

One of many chemicals made by glands in the body. Hormones circulate in the bloodstream and control the actions of certain cells or organs. Some hormones can also be made in the laboratory.

Hormones (estrogen, progesterone, or both) given to women after menopause to replace the hormones no longer produced by the ovaries. Also called HRT and menopausal hormone therapy.

In medicine, a process that makes pictures of areas inside the body. Imaging uses methods such as x-rays (high-energy radiation), ultrasound (high-energy sound waves), and radio waves.

In its original place. For example, in carcinoma in situ, abnormal cells are found only in the place where they first formed. They have not spread.

Cancer that has spread from where it started in the breast into surrounding, healthy tissue. Most invasive breast cancers start in the ducts (tubes that carry milk from the lobules to the nipple). Invasive breast cancer can spread to other parts of the body through the blood and lymph systems. Also called infiltrating breast cancer.

Cancer that begins in the lobules (the glands that make milk) of the breast. Lobular carcinoma in situ (LCIS) is a condition in which abnormal cells are found only in the lobules. When cancer has spread from the lobules to surrounding tissues, it is invasive lobular carcinoma. LCIS does not become invasive lobular carcinoma very often, but having LCIS in one breast increases the risk of developing invasive cancer in either breast.

A small lobe or a subdivision of a lobe.

A procedure in which radio waves and a powerful magnet linked to a computer is used to create detailed pictures of areas inside the body. These pictures can show the difference between normal and diseased tissue. Magnetic resonance imaging makes better images of organs and soft tissue than other scanning techniques, such as computed tomography (CT) or x-ray. Magnetic resonance imaging is especially useful for imaging the brain, the spine, the soft tissue of joints, and the inside of bones. Also called MRI, NMRI, and nuclear magnetic resonance imaging.

A term for diseases in which abnormal cells divide without control and can invade nearby tissues. Malignant cells can also spread to other parts of the body through the blood and lymph systems. There are several main types of malignancy. Carcinoma is a malignancy that begins in the skin or in tissues that line or cover internal organs. Sarcoma is a malignancy that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue. Leukemia is a malignancy that starts in blood-forming tissue such as the bone marrow, and causes large numbers of abnormal blood cells to be produced and enter the blood. Lymphoma and multiple myeloma are malignancies that begin in the cells of the immune system. Central nervous system cancers are malignancies that begin in the tissues of the brain and spinal cord. Also called cancer.

An x-ray of the breast.

A diagnostic indication that disease may develop.

Surgery to remove the breast (or as much of the breast tissue as possible).

A U.S. federal health insurance program for people aged 65 years or older and people with certain disabilities. Medicare pays for hospital stays, medical services, and some prescription drugs but people who receive Medicare must pay part of their healthcare costs.

Hormones (estrogen, progesterone, or both) given to women after menopause to replace the hormones no longer produced by the ovaries. Also called hormone replacement therapy and HRT.

The time of life when a woman’s ovaries stop producing hormones and menstrual periods stop. Natural menopause usually occurs around age 50. A woman is said to be in menopause when she hasn’t had a period for 12 months in a row. Symptoms of menopause include hot flashes, mood swings, night sweats, vaginal dryness, trouble concentrating, and infertility.

The monthly cycle of hormonal changes from the beginning of one menstrual period to the beginning of the next.

An instrument that is used to look at cells and other small objects that cannot be seen with the eye alone.

The National Cancer Institute, part of the National Institutes of Health of the United States Department of Health and Human Services, is the Federal Government's principal agency for cancer research. The National Cancer Institute conducts, coordinates, and funds cancer research, training, health information dissemination, and other programs with respect to the cause, diagnosis, prevention, and treatment of cancer. Access the National Cancer Institute Web site at http://www.cancer.gov. Also called NCI.

Fluid that is not milk coming from the nipple.

The taking in and use of food and other nourishing material by the body. Nutrition is a 3-part process. First, food or drink is consumed. Second, the body breaks down the food or drink into nutrients. Third, the nutrients travel through the bloodstream to different parts of the body where they are used as "fuel" and for many other purposes. To give the body proper nutrition, a person has to eat and drink enough of the foods that contain key nutrients.

Having an abnormally high, unhealthy amount of body fat.

Being too heavy for one’s height. Excess body weight can come from fat, muscle, bone, and/or water retention. Being overweight does not always mean being obese.

Describes the time in a woman’s life when menstrual periods become irregular as she approaches menopause. This is usually three to five years before menopause and is often marked by many of the symptoms of menopause, including hot flashes, mood swings, night sweats, vaginal dryness, trouble concentrating, and infertility.

A collection of information about a person’s health. It may include information about allergies, illnesses and surgeries, and dates and results of physical exams, tests, screenings, and immunizations. It may also include information about medicines taken and about diet and exercise. Also called personal health record and personal medical history.

Medical doctor.

A procedure in which a small amount of radioactive glucose (sugar) is injected into a vein, and a scanner is used to make detailed, computerized pictures of areas inside the body where the glucose is used. Because cancer cells often use more glucose than normal cells, the pictures can be used to find cancer cells in the body. Also called PET scan.

Having to do with the time after menopause. Menopause (“change of life”) is the time in a woman's life when menstrual periods stop permanently.

Having to do with the time before menopause. Menopause ("change of life") is the time of life when a woman's menstrual periods stop permanently.

In medicine, action taken to decrease the chance of getting a disease or condition. For example, cancer prevention includes avoiding risk factors (such as smoking, obesity, lack of exercise, and radiation exposure) and increasing protective factors (such as getting regular physical activity, staying at a healthy weight, and having a healthy diet).

Any natural or laboratory-made substance that has some or all of the biologic effects of progesterone, a female hormone.

The overall enjoyment of life. Many clinical trials assess the effects of cancer and its treatment on the quality of life. These studies measure aspects of an individual’s sense of well-being and ability to carry out various activities.

Energy released in the form of particle or electromagnetic waves. Common sources of radiation include radon gas, cosmic rays from outer space, medical x-rays, and energy given off by a radioisotope (unstable form of a chemical element that releases radiation as it breaks down and becomes more stable).

The use of high-energy radiation from x-rays, gamma rays, neutrons, protons, and other sources to kill cancer cells and shrink tumors. Radiation may come from a machine outside the body (external-beam radiation therapy), or it may come from radioactive material placed in the body near cancer cells (internal radiation therapy). Systemic radiation therapy uses a radioactive substance, such as a radiolabeled monoclonal antibody, that travels in the blood to tissues throughout the body. Also called irradiation and radiotherapy.

A doctor who specializes in creating and interpreting pictures of areas inside the body. The pictures are produced with x-rays, sound waves, or other types of energy.

The use of radiation (such as x-rays) or other imaging technologies (such as ultrasound and magnetic resonance imaging) to diagnose or treat disease.

The active ingredient in a drug used to reduce the risk of invasive breast cancer in postmenopausal women who are at high risk of the disease or who have osteoporosis. It is also used to prevent and treat osteoporosis in postmenopausal women. It is also being studied in the prevention of breast cancer in certain premenopausal women and in the prevention and treatment of other conditions. Raloxifene blocks the effects of the hormone estrogen in the breast and increases the amount of calcium in bone. It is a type of selective estrogen receptor modulator (SERM).

The organs involved in producing offspring. In women, this system includes the ovaries, the fallopian tubes, the uterus, the cervix, and the vagina. In men, it includes the prostate, the testes, and the penis.

Something that increases the chance of developing a disease. Some examples of risk factors for cancer are age, a family history of certain cancers, use of tobacco products, being exposed to radiation or certain chemicals, infection with certain viruses or bacteria, and certain genetic changes.

A person who has studied science, especially one who is active in a particular field of investigation.

Checking for disease when there are no symptoms. Since screening may find diseases at an early stage, there may be a better chance of curing the disease. Examples of cancer screening tests are the mammogram (breast), colonoscopy (colon), Pap smear (cervix), and PSA blood level and digital rectal exam (prostate). Screening can also include checking for a person’s risk of developing an inherited disease by doing a genetic test.

X-rays of the breasts taken to check for breast cancer in the absence of signs or symptoms.

A problem that occurs when treatment affects healthy tissues or organs. Some common side effects of cancer treatment are fatigue, pain, nausea, vomiting, decreased blood cell counts, hair loss, and mouth sores.

A procedure to remove or repair a part of the body or to find out whether disease is present. An operation.

One who remains alive and continues to function during and after overcoming a serious hardship or life-threatening disease. In cancer, a person is considered to be a survivor from the time of diagnosis until the end of life.

An indication that a person has a condition or disease. Some examples of symptoms are headache, fever, fatigue, nausea, vomiting, and pain.

A drug used to treat certain types of breast cancer in women and men. It is also used to prevent breast cancer in women who have had ductal carcinoma in situ (abnormal cells in the ducts of the breast) and in women who are at a high risk of developing breast cancer. Tamoxifen is also being studied in the treatment of other types of cancer. It blocks the effects of the hormone estrogen in the breast. Tamoxifen is a type of antiestrogen. Also called tamoxifen citrate.

A person trained in the techniques (methods) and skills of a profession. For example, a mammogram technician is trained to perform mammograms.

Treatment.

A group or layer of cells that work together to perform a specific function.

Having to do with poison or something harmful to the body. Toxic substances usually cause unwanted side effects.

An abnormal mass of tissue that results when cells divide more than they should or do not die when they should. Tumors may be benign (not cancer), or malignant (cancer). Also called neoplasm.

A procedure in which high-energy sound waves are bounced off internal tissues or organs and make echoes. The echo patterns are shown on the screen of an ultrasound machine, forming a picture of body tissues called a sonogram. Also called ultrasonography.

Fluid containing water and waste products. Urine is made by the kidneys, stored in the bladder, and leaves the body through the urethra.

A type of high-energy radiation. In low doses, x-rays are used to diagnose diseases by making pictures of the inside of the body. In high doses, x-rays are used to treat cancer.