- Estimating Breast Cancer Risk: Questions and Answers Center
- Breast Cancer Slideshow
- Take the Breast Cancer Quiz
- Breast Cancer Screening
- Patient Comments: Estimating Breast Cancer Risk - Experience
- Patient Comments: Estimating Breast Cancer Risk - Personal Risks
- 1. Who develops breast cancer?
- 2. What is the Breast Cancer Risk Assessment Tool?
- 3. What are the risk factors used to estimate breast cancer risk in the Breast Cancer Risk Assessment Tool?
- 4. Why are some other risk factors left out of the Tool?
- 5. Is the Breast Cancer Risk Assessment Tool useful for all women?
- 6. What are some of the latest research findings on breast cancer risk?
- 7. Are there ways to decrease the chance of developing breast cancer?
- 8. How did BCPT and STAR use the Breast Cancer Risk Assessment Tool to add to our knowledge of breast cancer risk?
- 9. What else can a woman do about breast cancer?
1. Who develops breast cancer?
Breast cancer is the most frequently diagnosed non-skin cancer in American women. An estimated 213,000 American women will be diagnosed with breast cancer in 2006. The risk of breast cancer increases as women get older. Over the years, researchers have identified certain characteristics, usually called risk factors, which influence a woman's chance of getting the disease. Still, many women who develop breast cancer have no known risk factors other than growing older, and many women with known risk factors do not develop breast cancer.
2. What is the Breast Cancer Risk Assessment Tool?
The Breast Cancer Risk Assessment Tool is a computer program that was developed by scientists at the National Cancer Institute and the National Surgical Adjuvant Breast and Bowel Project (NSABP) to assist health care providers in discussing breast cancer risk with their female patients. The tool allows a health professional to project a woman's individual estimate of breast cancer risk over a 5-year period of time and over her lifetime and compares the woman's risk calculation with the average risk for a woman of the same age. The Breast Cancer Risk Assessment Tool can be found at: http://www.cancer.gov/bcrisktool.
3. What are the risk factors used to estimate breast cancer risk in the Breast Cancer Risk Assessment Tool?
The risk factors included in the tool are:
- Personal history of breast abnormalities. Two breast tissue
abnormalities -- ductalcarcinoma in situ (DCIS) and lobular carcinoma in situ (LCIS) -- areassociated with increased risk for developing invasive breast cancer.
- Age. The risk of developing breast cancer increases with age. The majority of breast cancer cases occur in women older than age 50.
- Age at menarche (first menstrual period). Women who had their first menstrual period before age 12 have a slightly increased risk of breast cancer.
- Age at first live birth. Risk depends on age at first live birth and family history of breast cancer, as shown in the following table of relative risks.
|Age at first live birth||0 Affected Relatives||1 Affected Relatives||2 Affected Relatives|
|20 or younger||1||2.6||6.8|
|25-29 or no child||1.5||2.8||4.9|
|30 or older||1.9||2.8||4.2|
For women with 0 or 1 affected relative, risks increase with age at first live birth. For women with 2 or more first degree relatives, risks decrease with age at first live birth.
Adapted from Table 1, Gail MH, Brinton LA, Byar DP, Corle DK, Green SB, Shairer C, Mulvihill JJ: Projecting individualized probabilities of developing breast cancer for white females who are being examined annually. J Natl Cancer Inst 81(24):1879-86, 1989. [PubMed Abstract]
- Breast cancer among first-degree relatives (sisters, mother, daughters). Having one or more first-degree blood relatives who have been diagnosed with breast cancer increases a woman's chances of developing the disease.
- Breast biopsies. Women who have had breast biopsies have an increased risk of breast cancer, especially if the biopsy showed a change in breast tissue, known as atypical hyperplasia. These women are at increased risk because of whatever prompted the biopsies, not because of the biopsies themselves.
- Race. White women have greater risk of developing breast cancer than Black women (although Black women diagnosed with breast cancer are more likely to die of the disease).
Quick GuideBreast Cancer Diagnosis and Treatment
4. Why are some other risk factors left out of the Tool?
Other risk factors for breast cancer have been identified or proposed but are not included in the Breast Cancer Risk Assessment Tool for several reasons: because evidence that these factors contribute to breast cancer risk is not conclusive, because researchers cannot determine whether these factors add useful information to factors already in the model, or because data on other risk factors was not available in the research data used to develop the model. Such risk factors include: age at menopause, use of birth control pills, high body mass index, a high-fat diet, alcohol, radiation exposure, and environmental pollutants. Recently published research indicates that breast tissue density, measured from mammograms, can add useful information, but risk models with breast tissue density measurement still need to be validated with additional independent studies. Research also indicates that other risk factors, such as use of hormone therapy, might improve the tool.
5. Is the Breast Cancer Risk Assessment Tool useful for all women?
The Breast Cancer Risk Assessment Tool was developed for women in the United States population age 35 years or older. It should not be used for women with a previous diagnosis of breast cancer, women exposed to breast radiation for treatment of Hodgkin lymphoma, or women who reside in, or recently migrated from, regions with low breast cancer risk, such as rural China or Japan. More accurate methods to project risk may be available for women with certain rare identified mutations, such as alterations in the breast cancer susceptibility genes BRCA1 and BRCA2. The Breast Cancer Risk Assessment Tool was developed and has been validated in populations consisting mainly of non-Hispanic white women. More research is needed to validate or refine the model for other racial and ethnic groups.
6. What are some of the latest research findings on breast cancer risk?
Two studies in the September 6, 2006, issue of the Journal of the National Cancer Institute identified breast density as an important risk factor.* In one, a study of 11,638 women diagnosed with breast cancer, researchers identified different sets of risk factors in pre- and post-menopausal women. For pre-menopausal women, the risk factors included age, breast density, family history of breast cancer, and prior cancer diagnosis. For post-menopausal women, the risk factors included ethnicity, body mass index, age at natural menopause, use of hormone therapy, and a prior false-positive mammogram, in addition to all the risk factors for pre-menopausal women. The two separate models in this study for predicting breast cancer in pre- and post-menopausal women may be particularly helpful in identifying women at high risk for breast cancer.
The other study adds breast density and weight to the Gail model, a model that is the basis for the Breast Cancer Risk Assessment Tool (see Question 2). As before, the new model can be used to project risk over 5, 10, 20 and 30 year intervals. The new model predicted higher risks than the previous model in women with high breast density, and previous analyses indicated that the new model had modestly higher accuracy. Independent validation studies are needed before this model should be used for counseling, and before making a permanent change to the Breast Cancer Risk Assessment Tool.
7. Are there ways to decrease the chance of developing breast cancer?
Launched in April 1992, the Breast Cancer Prevention Trial (BCPT) was designed to see whether the drug tamoxifen could prevent breast cancer in women with an increased risk. Data reported in 1998 showed that both pre- and post-menopausal women taking tamoxifen had 49 percent fewer diagnosed cases of breast cancer. These results were also the first clear indication that a chemopreventive agent could be effective in preventing cancer in a high-risk population. For women over 50, tamoxifen was associated with serious side effects, such as endometrial cancer and blood clots. (http://www.cancer.gov/cancertopics/factsheet/Prevention/breast-cancer)
Starting in 1999, postmenopausal women ages 35 or older at increased risk for breast cancer participated in the Study of Tamoxifen and Raloxifene (STAR). The study compared tamoxifen with raloxifene, an osteoporosis drug. The initial results of the trial were announced on April 17, 2006 (see http://www.cancer.gov/newscenter/pressreleases/STARresultsApr172006), and showed that the drug raloxifene works as well as tamoxifen in reducing breast cancer risk for postmenopausal women at increased risk of the disease. In STAR, both drugs reduced the risk of developing invasive breast cancer by about 50 percent. In addition, within the study, women who were prospectively and randomly assigned to take raloxifene daily, and who were followed for an average of about four years, had 36 percent fewer uterine cancers and 29 percent fewer blood clots than the women who were assigned to take tamoxifen. Uterine cancers, especially endometrial cancers, are a rare but serious side effect of tamoxifen. Both tamoxifen and raloxifene are known to increase a woman's risk of blood clots. Data from STAR continues to be analyzed. (http://www.cancer.gov/newscenter/pressreleases/STARresultsQandA)
Quick GuideBreast Cancer Diagnosis and Treatment
8. How did BCPT and STAR use the Breast Cancer Risk Assessment Tool to add to our knowledge of breast cancer risk?
Both breast cancer prevention studies, BCPT and STAR, explored ways of reducing the risk of developing breast cancer; their findings have increased our knowledge of risk. Both trials involved women who have not had breast cancer, but were at high risk of developing it. BCPT used the Breast Cancer Risk Assessment Tool to determine eligible participants by projecting each woman's individualized estimate of breast cancer risk. The projections were accurate; thus the BCPT results validated the Breast Cancer Risk Assessment Tool. STAR researchers used the Breast Cancer Risk Assessment Tool for determining eligibility for enrollment. All STAR participants had to have an increased risk of breast cancer equivalent to or greater than that of an average 60- to 64-year-old woman.
9. What else can a woman do about breast cancer?
NCI recommends that women in their 40s and older get screening mammograms every one to two 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. Women also can take an active part in the early detection of breast cancer by having regular clinical breast exams (breast exams performed by health professionals).
Advances in screening have provided new tools for detection. In September of 2005, preliminary results from a large clinical trial of digital vs. film mammography found no difference in detecting breast cancer for the general populations of women in the trial. However, the Digital Mammographic Imaging Screening Trial (DMIST) found that women with dense breasts, who are pre- or perimenopausal (women who had a 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 regular film mammogram. More information about DMIST can be found at http://www.cancer.gov/newscenter/pressreleases/DMISTQandA.
Source: U.S. National Institutes of Health, National Cancer Institute, http://www.cancer.gov
Daily Health News
Subscribe to MedicineNet's Cancer Report Newsletter
Estimating Breast Cancer Risk - Experience
Please describe your experience with breast cancer.Post View 2 Comments
Estimating Breast Cancer Risk - Personal Risks
After using the tool, what is your breast cancer risk? Will it change your lifestyle or frequency of health exams?Post View 2 Comments
Estimating Breast Cancer Risk - Ways to Decrease
Have you been involved in any breast cancer prevention studies? If so, please share your experience.Post
Estimating Breast Cancer Risk - Screenings
What types of screenings, mammograms, or ultrasounds do you get to prevent breast cancer?Post
Top Estimating Breast Cancer Risk Related Articles
Alcohol Abuse and AlcoholismAlcoholism is a disease that includes alcohol craving and continued drinking despite repeated alcohol-related problems, such as losing a job or getting into trouble with the law. It can cause myriad health problems, including cirrhosis of the liver, birth defects, heart disease, stroke, psychological problems, and dementia. Counseling and a few medications can be effective for alcoholism treatment.
Birth Control Methods
Birth control is available in a variety of methods and types. The method of birth control varies from person to person, and their preferences to either become pregnant or not. Examples of barrier methods include:
- Barrier methods (sponge, spermicides, condoms)
- Hormonal methods (pill, patch)
- Surgical sterilization (tubal ligation, vasectomy)
- Natural methods
- The morning after pill
Side effects and risks of each birth control option should be reviewed prior to using any birth control method.
Breast BiopsyThere are several types of breast biopsies, which are diagnostic procedures to examine part or all of suspicious breast growth(s). The types of breast biopsies include fine needle aspiration breast biopsy (FNAB), core needle breast biopsy (CNB), vacuum-assisted breast biopsy, and excision breast biopsy (surgery, lumpectomy). The type of breast biopsy procedure depends upon the location and size of the growth(s).
Breast Cancer (Facts, Stages)Breast cancer is an invasive tumor that develops in the mammary gland. Breast cancer is detected via mammograms, breast self-examination (BSE), biopsy, and specialized testing on breast cancer tissue. Treatment of breast cancer may involve surgery, radiation, hormone therapy, chemotherapy, and targeted therapy. Breast cancer risk may be lowered by managing controllable risk factors.
Breast Cancer SlidesLearn about breast cancer causes, symptoms, tests, recovery, and prevention. Discover the types of treatments such as surgery and drug therapies as well as the survival rate for breast cancer.
Breast Cancer PreventionLifestyle changes, a healthy antioxidant-rich diet, exercise, and weight reduction can help reduce a woman's risk of developing breast cancer. It's important to be aware of how risk factors such as family history, lifestyle factors, breast conditions, radiation therapy, and hormonal factors may influence your chances of developing breast cancer. Mammography and breast self-examinations are crucial steps in breast cancer prevention.
CancerCancer is a disease caused by an abnormal growth of cells, also called malignancy. It is a group of 100 different diseases, and is not contagious. Cancer can be treated through chemotherapy, a treatment of drugs that destroy cancer cells.
Genetic Testing Families With Breast CancerBreast cancer can be a killer and the decision to get tested to see if a patient is prone to the disease should be discussed with a doctor -- particularly if the woman has a history of breast cancer in her family. Genetic testing can only tell so much about breast cancer risk, however.
Hormone TherapyEstrogen therapy, estrogen/progestin therapy, and hormone therapy are terms that refer to the administration of estrogen or estrogen/progestin for the purpose of suppressing hot flashes. Side effects of hormone therapy include:
- breast pain,
- blood clots,
- breast cancer,
- heart disease,
- abnormal vaginal bleeding,
- and uterine cancer.
MammogramMammogram is a test that produces an image of the breast tissue on film. The technique is referred to as mammography. Mammography can visualize normal and abnormal structures within the breast such as cysts, calcifications, and tumors looking for breast cancer. The first baseline mammogram for a woman should be between the ages of 35 to 40.
MenopauseMenopause is the time in a woman's life when menstrual periods permanently stop, also called the "change of life." Menopause symptoms include hot flashes, night sweats, irregular vaginal bleeding, vaginal dryness, painful intercourse, urinary incontinence, weight gain, and emotional symptoms such as mood swings. Treatment of menopausal symptoms varies, and should be discussed with your physician.
Nature vs Nurture Theory Genes or Environment
In the nature vs. nurture debate, "nature" represents our genetic makeup. These are the genes you have inherited from your biological family, and that may affect your physical and mental health, for example, intelligence, disease, and psychological health. While "nurture" represents how our environment effects our intelligence, traits, personality, and mental and physical health. Studies have shown that a person's environment can alter his or her genes, and lower their risk of developing certain inherited diseases, conditions, and mental illnesses that run in his or her family.
Hippocrates studied and theorized how our biology affected our overall health and disease development. In 1869, Sir Francis Galton was credited for the term "Nature vs. Nurture Theory." Today it is widely recognized that both your genes and your environment effect both your physical and mental health.
Researchers and doctors have found that particular physical traits like eye and skin color, and diseases like Huntington's chorea are the result of genetic inheritance (inherited from a family member). However, patterns of thinking and behavior can be attributed to both nature and nurture (your genes and your environment). Moreover, researchers who study the brain have found overwhelming evidence that a person's genetic factors and his or her experiences guide and support brain development. The human brain produces new nerve cells (neurons) into adulthood, and these nerve cells can change the strength of their connections throughout life, which can effect intelligence and other factors. Research also has shown that sensory input (sights, smells, sounds, touch, etc.) has a critical in the role of brain development in the first few days of our lives, and probably throughout our life.
The controversy over how much our genes and environment effect our psychological and physical health still continues, however.
NCBI. PubMed.gov. Brain development and the nature versues nurture debate. Prog Brain Res. 2011;189:3-22. doi: 10.1016/B978-0-444-53884-0.00015-4.
NCBI Resources. Institute of Medicine (US) Forum on Neuroscience and Nervous System Disorders. Washington (DC): National Academies Press (US); 2008.
Evista (raloxifene) is a medication that is prescribed for the treatment and prevention of osteoporosis in postmenopausal women. Black box warnings for Evista includes
- an increased risk of deep vein thrombosis (DVT),
- pulmonary embolism, and
Other side effects, drug interactions, dosage, and pregnancy and breastfeeding safety information should be reviewed prior to taking this medication.
Tamoxifen (Soltamox) is an anti-estrogen medication prescribed for the prevention and treatment of breast cancer in men and breast cancer in women. Tamoxifen also is prescribed to stimulate ovulation. Side effects include:
- Fluid retention
- Bone pain
Drug interactions, dosing, and pregnancy and breastfeeding safety should be reviewed prior to taking any medication. Nolvadex brand has been discontinued.
Normal vaginal bleeding (menorrhea) occurs through the process of menstruation. Abnormal vaginal bleeding in women who are ovulating regularly most commonly involves excessive, frequent, irregular, or decreased bleeding. Causes of abnormal may arise from a variety of conditions that may include:
- Uterine fibroids
- Pelvic inflammatory disease
- Emotional stress
- Anorexia nervosa
- Polycystic ovary syndrome (PCOS)
- Early pregnancy
The treatment for abnormal or irregular vaginal bleeding depends upon the cause.
Women's HealthWomen's health is an important topic area to guide a woman through the stages of her life, as well as knowing the conditions and diseases that may occur. Educating yourself so that the transitions into different phases of life is key to a healthy, happy, and productive life.