While breast cancer is sometimes found after symptoms appear, many women with early breast cancer have no symptoms of the disease. This is why getting the recommended screening tests (as described in “Can breast cancer be found early?”) before any symptoms develop is so important.
If something suspicious is found during a screening exam, or if you have any of the symptoms of breast cancer described below, your doctor will use one or more methods to find out if the disease is present. If cancer is found, other tests will be done to determine the stage (extent) of the cancer.
Signs and symptoms
Although widespread use of screening mammograms has increased the number of breast cancers found before they cause any symptoms, some breast cancers are not found by mammogram, either because the test was not done or because, even under ideal conditions, mammograms do not find every breast cancer.
The most common sign of breast cancer is a new lump or mass. A painless, hard mass that has irregular edges is more likely to be cancerous, but breast cancers can be tender, soft, or rounded. For this reason, it is important that any new breast mass or lump be checked by a health care professional experienced in diagnosing breast diseases.
Other possible signs of breast cancer include:
* swelling of all or part of a breast (even if no distinct lump is felt)
* skin irritation or dimpling
* breast or nipple pain
* nipple retraction (turning inward)
* redness, scaliness, or thickening of the nipple or breast skin
* a discharge other than breast milk
Sometimes a breast cancer can spread to underarm lymph nodes and cause a lump or swelling there, even before the original tumor in the breast tissue is large enough to be felt.
Medical history and physical exam
If you have any signs or symptoms that might be due to breast cancer, be sure to see your doctor as soon as possible. Your doctor will ask you questions about your symptoms, any other health problems, and possible risk factors for benign breast conditions or breast cancer.
Your breasts will be thoroughly examined for any lumps or suspicious areas and to feel their texture, size, and relationship to the skin and chest muscles. Any changes in the nipples or the skin of your breasts will be noted. The lymph nodes in the armpit and above the collarbones may be palpated (felt), because enlargement or firmness of these lymph nodes might indicate spread of breast cancer. Your doctor may also do a complete physical exam to judge your general health and whether there is any evidence of cancer that may have spread.
If breast symptoms and/or the results of your physical exam suggest breast cancer might be present, more involved tests will likely be done. These might include imaging tests, looking at samples of nipple discharge, or doing biopsies of suspected areas.
Imaging tests used to evaluate breast disease
Imaging tests use x-rays, magnetic fields, sound waves, or radioactive substances to create pictures of the inside of your body. Imaging tests may be done for a number of reasons, including to help find out whether a suspicious area might be cancerous, to learn how far cancer may have spread, and to help determine if treatment has been effective.
Diagnostic mammograms
Although mammograms are mostly used for screening, they can also be used to examine the breast of a woman who has a breast problem. This can be a breast mass, nipple discharge, or an abnormality that was found on a screening mammogram. In some cases, special images known as cone views with magnification are used to make a small area of abnormal breast tissue easier to evaluate.
A diagnostic mammogram can show:
* That the abnormality is not worrisome at all. In these cases the woman can usually return to having routine yearly mammograms.
* That a lesion (area of abnormal tissue) has a high likelihood of being benign (not cancer). In these cases, it is common to ask the woman to come back sooner than usual for her next mammogram, usually in 4 to 6 months
* That the lesion is more suspicious, and a biopsy is needed to tell if it is cancer.
Even if the mammograms show no tumor, if you or your doctor can feel a lump, then usually a biopsy will be needed to make sure it isn’t cancer. One exception would be if an ultrasound exam finds that the lump is a simple cyst (a fluid-filled sac), which is very unlikely to be cancerous.
Digital mammograms: A digital mammogram (also known as a full-field digital mammogram, or FFDM) is like a standard mammogram in that x-rays are used to produce an image of your breast. The differences are in the way the image is recorded, viewed by the doctor, and stored. Standard mammograms are recorded on large sheets of photographic film. Digital mammograms are recorded and stored on a computer. After the exam, the doctor can look at them on a computer screen and adjust the image size, brightness, or contrast to see certain areas more clearly. Digital images can also be sent electronically to another site for a remote consult with breast specialists. While many centers do not offer the digital option at this time, it is expected to become more widely available in the future.
Because digital mammograms cost more than standard mammograms, studies are now under way to determine which form of mammogram will benefit more women in the long run. Some studies have found that women who have a FFDM have to return less often for additional imaging tests because of inconclusive areas on the original mammogram. A recent large study found that a FFDM was more accurate in finding cancers in women younger than 50 and in women with dense breast tissue, although the rates of inconclusive results were similar between FFDM and film mammograms. It is important to remember that a standard film mammogram also is effective for these groups of women, and that they should not miss their regular mammogram if a digital mammogram is not available.
Computer-aided detection and diagnosis (CAD): Over the past 2 decades, computer-aided detection and diagnosis (CAD) has been developed to help radiologists detect suspicious changes on mammograms. This can be done with standard film mammograms or with digital mammograms.
Computers can help doctors identify abnormal areas on a mammogram by acting as a second set of “eyes.” For standard mammograms, the film is fed into a machine which converts the image into a digital signal that is then analyzed by the computer. Alternatively, the technology can be applied to a digital mammogram. The computer then displays the image on a video screen, with markers pointing to areas that the radiologist should check especially closely.
It’s not yet clear how useful CAD is. Some doctors find it helpful, but a recent large study found it did not significantly improve the accuracy of breast cancer detection. It did, however, increase the number of women who needed to have breast biopsies. Further research of this approach is needed.
Magnetic resonance imaging (MRI) of the breast
MRI scans use radio waves and strong magnets instead of x-rays. The energy from the radio waves is absorbed and then released in a pattern formed by the type of body tissue and by certain diseases. A computer translates the pattern into a very detailed image of parts of the body. A contrast material called gadolinium is often injected into a vein before or during the scan to show details better.
MRI scans can take a long time — often up to an hour. You have to lie inside a narrow tube, which is confining and may upset people with claustrophobia (a fear of enclosed spaces). The machine also makes loud buzzing and clicking noises that you may find disturbing. Some places provide headphones with music to block this out. MRIs are also expensive, although insurance plans generally pay for them in some situations, such as once cancer is diagnosed.
Although MRI machines are quite common, they need to be specially adapted to look at the breast. It’s important that MRI scans of the breast be done on one of these specially adapted machines.
MRI can be used along with mammograms for screening women who have a high risk of developing breast cancer, or it can be used to better examine suspicious areas found by a mammogram. MRI is also used for women who have been diagnosed with breast cancer to better determine the actual size of the cancer and to look for any other cancers in the breast.
Breast ultrasound
Ultrasound, also known as sonography, uses sound waves to outline a part of the body. For this test, a small, microphone-like instrument called a transducer is placed on the skin (which is often first lubricated with ultrasound gel). It emits sound waves and picks up the echoes as they bounce off body tissues. The echoes are converted by a computer into a black and white image that is displayed on a computer screen. This test is painless and does not expose you to radiation.
Ultrasound has become a valuable tool to use along with mammography because it is widely available and less expensive than other options, such as MRI. The use of ultrasound instead of mammograms for breast cancer screening is not recommended. Usually, breast ultrasound is used to target a specific area of concern found on the mammogram. Ultrasound helps distinguish between cysts (fluid-filled sacs) and solid masses and between benign and cancerous tumors.
Ultrasound may be most helpful in women with very dense breasts. Clinical trials are now looking at the benefits and risks of adding breast ultrasound to screening mammograms in women with dense breasts and a higher risk of breast cancer.
Ductogram
This test, also called a galactogram, is sometimes helpful in determining the cause of nipple discharge. In this test a very thin plastic tube is placed into the opening of the duct in the nipple. A small amount of contrast medium is injected, which outlines the shape of the duct on an x-ray image and shows if there is a mass inside the duct.