Common examinations to detect breast cancer include the breast self-exam, the breast exam by a professional, mammography, ultrasonography, magnetic resonance imaging, and positron emission tomography.
Breast Self-Exam
The value of breast self-examination (BSE) has been evaluated in several trials. Results from a large study conducted in China have recently been published in the Journal of the National Cancer Institute (J Natl Cancer Inst 2002;94:1445-57). In the study, women who performed BSE every 4-5 months did not have a lower death rate from breast cancer compared to those who did not. The authors point out that highly motivated women who perform the exam proficiently monthly may discover cancers that develop between regular mammographic screenings. Furthermore, these cancers might be at an earlier, more curable stage than if the only screening activities were yearly mammograms with a clinical breast exam.
Whether or not you elect to perform regular breast exams, it remains important to be familiar with the way your breasts feel and look. Many women who develop breast cancer find it themselves by recognizing a new lump while they are bathing.
Breast self-exam should begin at age 20 and should be performed five to seven days after the menstrual period begins. Your breasts will be less swollen and tender at that time and it will be easier to detect abnormalities. If you no longer menstruate, choose a particular day of the month to do BSE, such as the first of the month.
A breast self-exam is easiest done in the shower, when your breasts and hands are soapy. Use the pads of three fingers to check your breast for lumps, applying moderate pressure to feel for anything out of the ordinary. Check each area again using lighter and firmer pressure. Move your fingers across the breast in a pattern, such as circles or rows. Check the entire breast area, as well as under your arm, up to your collarbone, and below your breasts. Once you have finished showering, repeat the examination lying down on your bed. Also, with both arms over your head, look in the mirror for any changes such as puckering, redness, swelling, or changes in size or shape. Do the same with your hands on your hips. If you detect any of these changes, or if you do find a suspicious mass while examining your breasts, whether or not it's painful, bring it to the attention of your doctor. If you are unsure of the technique, ask your doctor to show you while you are getting a clinical examination. Ask for a brochure that explains how to do a self-examination.
Clinical Breast Exam
Women aged 20 to 39 are advised to have a clinical breast exam - one performed by a doctor or other health care provider - every three years. Those 40 and older should have the exam every year.
The clinical breast exam is similar to the breast self-exam in that the health care provider will gently feel each area of the breast for lumps. He or she will also examine the armpits and above the collarbone to look for enlarged lymph glands.
Mammography
In October 2001, an article was published in The Lancet (358;1340-1342) in which the authors questioned the value of mammograms for screening in terms of identifying cancers at early curable stages. Several authoritative bodies have recently carefully re-evaluated the value of mammography, taking all available evidence, including critiques, into account. On the basis of this intense examination, all impartial authorities, including the National Cancer Institute (NCI) and the U.S. Department of Health and Human Services (HHS), continue to recommend screening mammography. The NCI and the Department of HHS advise biyearly mammograms for women between the ages of 40 and 49 and yearly or bi-yearly exams after the age of 50.
Properly done, a mammogram can detect 85 to 90 percent of all breast cancers, and may detect cancers too small to be felt.
A mammogram is simply an x-ray of the breast. During a mammogram you stand in front of a special x-ray machine and one breast at a time is placed on a flat plate that sits perpendicular to your body. A second plate is lowered on top of the breast and compresses it, making the breast flatter. An x-ray is taken while the breast is compressed. A mammogram uses very low levels of radiation.
To get the best picture possible, schedule your mammogram for the first half of your menstrual cycle, the 14 days following the start of a period. Your breasts may be less swollen and tender at that time. This is especially true in women in their 40s, who tend to have denser breasts than older women. Avoid using deodorant or talcum powder on the day of the exam, as these can distort the results.
The x-ray will be developed and given to a radiologist to read and interpret. If you have had one or more mammograms at other facilities in the past, bring those x-rays with you on the day of your appointment so the radiologist can compare them and look for changes. The radiologist may decide to take extra pictures if there are any areas that are suspicious or need to be clarified. The radiologist is required by law to notify you of the results in writing, using easy-to-understand language.
A new mammography technique is being studied to see if it is an improvement on the standard mammogram. Digital mammography uses a computer to convert the image of the breast into digital output. This may make it easier to evaluate "dense" tissue and may make it possible to magnify areas of the breast for better inspection.
Ultrasound Examination
The radiologist may suggest an ultrasound examination if something unusual is noted on your screening mammogram, or your doctor may suggest an ultrasound if the physical examination reveals something unusual.
An ultrasound uses sound waves to create an image of breast tissue. There is no radiation. It can clearly identify a harmless fluid-filled cyst, eliminating the need for a biopsy. If a solid mass is identified, a biopsy may be recommended.
During the test, a harmless gel is first spread on the skin. A hand-held transducer is then slowly passed over the breast; it emits sound waves that bounce off tissues and back to the transducer. The examination is painless; all you feel is light pressure from the transducer.
A radiologist will interpret the results of the examination.
Magnetic Resonance Imaging (MRI)
An MRI of the breast may be recommended to further analyze changes seen on the mammogram or sonogram. It may also be used when a woman has implants in order to prevent the implant from rupturing.
An MRI uses a very large magnet, rather than radiation, to detect differences in tissues. During the exam you will lie on a table that slides into a machine that contains the magnet. The magnet then causes certain elements in your body's cells to line up. Another device in the machine causes these elements to briefly wobble out of position. As they return to their lined-up position, the elements emit radio waves of various strengths. These waves are detected by the machine and are translated into an image on a computer. Sometimes a dye is injected into the bloodstream to enhance the images.
An MRI is painless, but some people are uncomfortable with the noise of the machine or having to stay still in a tube. Ask the technician if you can have earplugs or listen to music during the procedure. Also, you can talk to the technician at all times during the procedure.
