Breast Cancer Screening
Breast Self-Examination
Clinical Breast Examination
Mamography
Risk Factors for Breast Cancer
The goal of a breast cancer screening program is to detect breast cancers at the earliest possible time in order to increase the likelihood of survival and to minimize disruption to a patient's life. Ideally, breast cancers will be detected before the cancer cells have a chance to invade surrounding tissue and gain access to the bloodstream. This preinvasive form of breast cancer is called ductal carcinoma in situ (DCIS) and is completely curable with appropriate treatment. Before widespread use of screening mammography, DCIS accounted for less than 5 percent of all breast cancers diagnosed. Currently, DCIS accounts for up to 25 percent of all breast cancers diagnosed. DCIS can be detected on mammography because of its tendency to create tiny calcium deposits in the milk ducts (called calcifications) that are visible on x-rays.
Unfortunately, not all DCIS creates these calcifications, so many cancers cannot be seen on mammograms until they invade surrounding breast tissue and form a mass. (At this stage they are called an invasive or infiltrating breast cancer.) The smaller the mass, the better the chance of being cured. Mammography is capable of identifying masses that are too small to be felt either by a woman or her doctor. However, while mammography remains the best method for early detection of breast cancer, up to 10 percent of breast cancers are not visible on a mammogram and will only be detected when they cause a change in the feel or appearance of the breast.
For these reasons, we believe that breast cancer screening should include three components: Breast Self Examination (BSE), Clinical Breast Examination (CBE), and Mammography.
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Because not all cancers are visible on mammograms, we believe that BSE should remain an important part of breast cancer screening. The idea behind BSE is for you to get to know what your breasts look and feel like so that you can notice any subtle changes that may represent an early cancer. Many women dislike performing BSE because they always feel some lumpiness. This is quite normal. Most women’s breasts have some degree of irregularity as a result of hormonal influences. As you get into the habit of regular BSE, however, you will get to know what is normal for you and you will be able to detect changes. Typically, cancers feel quite different from the usual lumps and bumps found in normal breast tissue.
A complete breast self-examination should be performed on a monthly basis, preferably during the one to two weeks after the start of your period (if you are still menstruating). The exam has three parts:
1) Standing in front of a mirror with your arms at your sides, look carefully for changes in the size, shape, and contour of your breasts. Look for puckering, dimpling, or changes in the skin color or texture. Repeat with your arms raised over your head. 
2) While lying down with a pillow under your right shoulder and your right hand behind your head, examine your breast with your left hand. With your fingers flat, gently press in a circular motion, starting at the outside top edge and spiraling inward towards the nipple. Be sure to include your underarm and the areas above and below the breast. Repeat this procedure on the left side. 
3) While in the shower, raise your right arm over your head and again use your left hand to examine your right breast. This works best with soapy hands. With the flat part of your fingers and using a circular motion, touch every part of your breast, including the underarm, gently feeling for a lump or thickening. Repeat this procedure on the left side. If you notice any significant changes, contact your physician immediately.Back to top
Women should undergo breast examination by a clinician as part of their normal health maintenance program. This should be done every two to three years from age 20 to 40, and annually after the age of 40. The CBE has the same limitations as BSE in that a cancer will only be recognized after it grows large enough to be felt, whereas mammography can detect cancers when they are too small to be felt. However, not all cancers can be detected by mammography. BSE and CBE are used to detect the cancers that are missed on mammograms.
Clinicians have experience with the sometimes subtle changes associated with breast cancer and so a cancer may be detected on CBE that was missed on BSE. On the other hand, a woman has more opportunity to get to know her own breasts and their unique density and texture, so she may be better able to detect subtle changes than a clinician who only examines the woman’s breasts on an annual basis. Therefore, CBE and BSE are complimentary techniques and can only add to the effectiveness of mammography as a screening tool.
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The current recommendations for screening mammography are for women to undergo 4-view (2 xray views of each breast) mammography on an annual basis beginning at the age of 40. If abnormalities are noted, other breast imaging studies (including special mammographic views, ultrasound, or MRI) or a biopsy may be indicated as part of a “diagnostic” work-up.
Women who are at increased risk for developing breast cancer should discuss with their physicians whether they should begin screening at a younger age or if they should undergo more frequent or different screening regimens.
Currently, breast ultrasound and breast MRI are not recommended for screening unless special circumstances exist.
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Breast Cancer Screening Links
American Cancer Society Updated Breast Cancer Screening Guidelines
National Cancer Institute information on Screening for Breast Cancer
Risk Factors for Breast Cancer
There are number of well-established risk factors for breast cancer, and much current research is focused on identifying additional personal and environmental factors which may increase a woman's susceptibility to breast cancer.
Risk Factors and Breast Cancer |
| Factors that increase risk |
| Increasing Age Early Age of Onset of Menstrual Periods Late Menopause Use of Postmenopausal Estrogen Replacement Therapy Proliferative Breast Disease Family History: Members with Early Onset of Disease Multiple First-Degree Relatives with Breast Cancer Breast Cancer Genes (BRCA1 and BRCA2) Post-menopausal Obesity First Pregnancy after age 30, or No Pregnancies Dense Breasts on Mammography Ionizing Radiation Exposure Smoking Heavy Alcohol Intake |
| Factors that decrease risk |
| Irregular Menses, with long intervals between periods Regular exercise Breast feeding First full-term pregnancy before age 30 |
Most recently, researchers from Denmark have investgated the relationship
between growth patterns and breast cancer risk (New England Journal of
Medicine, October 14, 2004: 351:1619-1626). The review of 117, 415 Danish
women found that birth weight, high stature at age 14, low body-mass index
at 14 years of age, and high growth rates around puberty, were independent
risk factors for breast cancer.
Many of these risk factors will be discussed with your surgeon at the time
of your evaluation. Long uninterrupted exposure to estrogen is considered
a significant risk factor, whether it is the additional use of estrogen
replacement after menopause, or a prolonged stretch of uninterrupted menstrual
cycles due to early onset of menses without pregnancy, or pregnancy later
in reproductive life.
Your physician may assess your risk using various models, or risk predictors. The best known is the Gail model, which includes age, age at onset of menses, age at first live birth, number of benign breast biopsies, and history of breast cancer in first degree relatives.
There are a number of hereditary breast cancer syndromes, with a specific pattern of breast cancer and associated cancers seen in family members. This is why your doctor will take a detailed family history from you, to see if your family fits one of these patterns. It is important to remember however, that the majority of breast cancers detected (about 90% in the United States) are sporadic, not familial or hereditary cases.
If you have afamily history of multiple members with breast, ovarian prostate, or male breast cancer, or you have been diagnosed with breast cancer at a young age, you may be referred to the Genetics Service for counseling regarding the risk of possible hereditary breast cancer, and discussion regarding genetic testing for specific breast cancer genes. The BRCA 1 and BRCA 2 genes have been associated with breast cancer in these settings.
