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DIAGNOSING BENIGN BREAST CHANGES
If the possibility of breast cancer or benign breast disease has been suggested by screening tests or by a woman’s symptoms, the doctor will use one or more methods to find out which is present so that the most appropriate treatment can be chosen.
Medical history and physical exam
The first step is a medical history and physical examination. Personal and family medical history will provide information about symptoms and risk factors for breast cancer and benign breast conditions. A thorough breast physical examination will be done to locate any lump and feel its texture, size, and relationship to the skin and chest muscles. Any changes in the nipples or the skin of the breast will be noted. The lymph nodes under the armpit and above the collarbones may be felt because enlargement or firmness of these lymph nodes might indicate spread of breast cancer. In addition to the medical history and physical exam, imaging tests and biopsies may be done.
Imaging tests for breast disease diagnosis
The two main imaging tests for breast diagnosis are mammography and ultrasound examination. For information about these and other imaging tests, refer to the American Cancer Society document on Mammography and other Breast Imaging Tests.
Diagnostic mammography: Diagnostic mammography is an x-ray examination of the breast of a woman who has a breast complaint (for example, a breast mass or nipple discharge) or who has an abnormality that was found on a routine screening mammogram. The two main types of abnormalities doctors look for on mammograms are masses and calcifications. Masses can be due to a cancer or a benign condition. Their size, shape, and edges help doctors judge whether a mass is likely to be a cancer. Calcifications are tiny mineral deposits in the breast tissue that appear as small white spots in the films. Most calcifications are due to benign changes. Microcalcifications (spots smaller than 1/50 of an inch) raise the possibility of cancer when they occur in clusters. 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 mammography work-up may show that a lesion (area of abnormal tissue) has an extremely high likelihood of being benign (not cancer). For these, it is common to ask the woman to come back sooner than usual for a recheck, usually in 4-6 months. On the other hand, a diagnostic mammogram may show that the abnormality is not worrisome at all and the woman can then return to routine yearly screening. Finally, the diagnostic work-up may suggest that a biopsy is needed to tell whether or not the lesion is a cancer or a type of benign breast disease requiring surgical treatment.
Breast ultrasound: Ultrasound, also known as sonography, uses high-frequency sound waves to outline a part of the body. High-frequency sound waves are transmitted through the area of the body being studied. The sound wave echoes are picked up and converted by a computer into an image that is displayed on a computer screen. No radiation exposure occurs during this test. Breast ultrasound is sometimes used to evaluate breast abnormalities that are found during mammography or a physical exam. Ultrasound is useful for some breast masses and is the only way to tell if a fluid-filled cyst is present without placing a needle into it to draw out fluid.
Nipple discharge examination
If there is a nipple discharge, some of the fluid may be collected and, after being smeared onto glass slides, examined under a microscope to see if any cancer cells are present. Most nipple discharges or secretions are not cancer. In general, if the secretion appears clear or milky, yellow, or green, cancer is very unlikely.
If the discharge is red or red-brown, suggesting that it contains fresh blood or old blood, it might be due to cancer, although infections or benign tumors are much more likely causes. Even when no cancer cells are found in a nipple discharge, it is not possible to say for certain that a breast cancer is not present. If a patient has a suspicious mass, a biopsy is necessary, even if the nipple smear does not contain cancer cells.
A ductogram also called a galactogram, is another test that is sometimes helpful in determining the cause of a nipple discharge. This is a type of x-ray test in which a fine plastic tube is placed into the opening of the duct onto the nipple. A small amount of contrast medium is injected, which outlines the shape of the duct on an x-ray picture and will show whether there is a mass inside the duct.
If the discharge is not bloody, doctors may not send the fluid to the lab for microscopic examination, particularly if the patient’s symptoms, her physical exam findings, and the color of the discharge suggest a benign condition rather than cancer.
Biopsy
A biopsy may be done when something unusual is found by mammography, ultrasound or physical examination. A biopsy is the only way to tell if cancer or a benign breast tumor is really present. All biopsy procedures remove a tissue sample for examination under a microscope. There are several types of biopsies, and each has distinct advantages and disadvantages. The choice of which to use depends on each patient's situation. Some of the factors the physician will consider include how suspicious the lesion appears, how large it is, where in the breast it is located, how many lesions are present, other medical problems the patient may have, and her personal preferences. Women are encouraged to discuss the advantages and disadvantages of different biopsy procedures with their doctors.
Fine needle aspiration biopsy (FNAB): FNAB uses a thin needle, which is even smaller than the needle used for blood tests. The needle can be guided into the area of the breast abnormality while the doctor is palpating (feeling) the lump. If the lump can’t be felt easily, the doctor might use ultrasound or a method called stereotactic needle biopsy to guide the needle. With ultrasound, the doctor can watch the needle on a screen as it moves toward and into the mass. For stereotactic needle biopsy, computers map the exact location of the mass using mammograms taken from two angles. Then the computer guides the needle to the right spot.
Once the needle is in place, fluid can often be drawn out if any is present. Bloody or cloudy fluid can mean either a benign cyst or cancer. If the lump is solid, small tissue fragments are drawn out. Solid lumps may be due to cancer or to several types of benign breast conditions. Cells from the cyst fluid or small tissue fragments from a solid mass are sent to the lab, where they are placed onto glass slides and treated with stains t make them more visible under the microscope. Microscopic examination of FNAB samples can tell whether most breast abnormalities are benign or cancerous. In some cases, FNAB does not provide a clear answer and another type of biopsy is needed.
Triple test: This is not an actual test or procedure. It is a way of correlating the results of the breast physical examination, mammography, and the FNA biopsy. If all three of these appear benign, the lesion can indeed be considered to be benign with about 98% accuracy. If any one of these is in disagreement, additional testing (needle core biopsy or surgical biopsy) should be performed.
Core needle biopsy: The needle used in core biopsies is larger than that used in FNA biopsy. It removes a small cylinder of tissue (about 1/16 inch in diameter and ½ inch long) from a breast abnormality. The biopsy is done with local anesthesia in the doctor's office or clinic. As with FNA biopsy, a core biopsy can sample abnormalities felt by the doctor as well as smaller ones pinpointed by ultrasound or stereotactic methods.
Surgical biopsy: In some cases, surgery may be needed to remove all or part of the lump for microscopic examination. An excisional biopsy is used to remove an entire lesion (breast abnormality such as a lump or area containing calcifications) as well as a surrounding margin of normal-appearing breast tissue. This biopsy usually can be done in the hospital outpatient department under a nongeneral anesthesia with intravenous sedation or local anesthesia where the woman is awake during the procedure, or in doctor's office.
The surgeon may use a procedure called a wire localization during an excisional breast biopsy of a small lump that is hard to locate by touch or for areas that look suspicious on the x-ray (due to calcifications, for example) but do not have a distinct lump. After numbing the area with local anesthetic, a thin hollow needle is placed into the breast and x-ray pictures are taken to guide the needle to the suspicious area. A thin wire is inserted through the center of the needle. A small hook at the end of the wire keeps it in place. The hollow needle is then removed, and the surgeon uses the wire as a guide to locate the abnormal area to be removed.
Other stereotactic biopsy methods: The Mammotome and ABBI are two new instruments for removing stereotactic breast biopsies. One potential disadvantage of fine needle and core biopsy methods for biopsy of abnormalities found by mammography (such as microcalcifications) is that they remove only a small sample of tissue from the abnormality. If the biopsy finds cancer, it can be assumed to be accurate. But, if no cancer is found, there may be some uncertainty as to whether the needle point missed the target. Until recently, an excisional biopsy with wire localization was the only way to remove all or most of a non-palpable (seen on mammography but cannot be felt) area of abnormal tissue containing microcalcifications. During the past few years, two new devices have been invented that can be guided by stereotactic methods and can remove more tissue than a core biopsy. The Mammotome, also known as vacuum-assisted biopsy, uses suction to draw tissue into an opening in the side of a cylinder inserted into the breast tissue. A rotating knife then cuts the tissue samples from the rest of the breast. This method usually removes about twice as much tissue as core biopsies. The ABBI method (short for Advanced Breast Biopsy Instrument) uses a rotating circular knife, and a thin wire heated by electrical current to remove a large cylinder of tissue containing the abnormality. The amount of tissue sampled with the ABBI is usually much greater than with the Mammotome. Both the Mammotome and ABBI instruments have been recently approved by the US Food and Drug Administration (FDA) for use in diagnosis of breast abnormalities. But, breast specialists still disagree about when each of these instruments should be used for diagnosis of non-palpable abnormalities, and whether some should be used at all.
FIBROCYSTIC CHANGES
Fibrocystic change includes a range of changes within the breast involving both the glandular and stromal components. In the past, people referred to this as "fibrocystic disease". Because this condition affects at least half of all women at some point in their lives, it is more accurately defined as a "change" rather than a "disease". Fibrocystic changes are most common in women of child-bearing age, but can affect women of any age.
Diagnosis of fibrocystic changes
In most cases, this condition is recognized by its typical symptoms - cysts, lumpiness, areas of thickening, tenderness, or pain. Cysts often enlarge and become painful just before the menstrual period, because they are influenced by monthly hormonal changes and tend to be prominent just before the menstrual period begins. Sometimes, one of the lumps may be particularly firm or have other features raising the possibility of cancer being present. When this occurs, a needle biopsy or a surgical biopsy may be necessary to be certain that cancer is not present.
Significance of Microscopic Features in some Cases of Fibrocystic Changes
When breast tissue affected by fibrocystic change is viewed under the microscope, a wide variety of changes may be noted. Most of these changes merely reflect the way the woman’s breast tissue has responded to monthly hormonal changes, and have little other importance. However, some changes may indicate slightly or moderately increased risk of developing breast cancer later on. By understanding some of the terms doctors use in describing these changes, a woman can better understand their degree of seriousness and whether extra measures for early breast cancer detection are needed.
Fibrosis: As the term "fibrocystic" suggests, the two main features are fibrosis and cysts. Fibrosis refers to the prominence of fibrous tissue, the same material that ligaments and scar tissue are made of. Areas of fibrosis feel "rubbery", firm, or hard to the touch. Fibrosis has no impact on a woman’s breast cancer risk and does not require any special treatment.
Cysts: Cysts are fluid-filled spaces lined by breast glandular cells. They start out as accumulation of fluid inside breast glands. Microcysts are too small to feel, and are found only when tissue is viewed under the microscope. If fluid continues to build up, macroysts are formed. These can be easily felt and may reach one or two inches across. As they grow, stretching of the surrounding breast tissue may cause pain. A round, movable lump, especially one that is tender to the touch is very suggestive of a cyst. Breast ultrasound is often used to confirm this impression. Fine needle aspiration can confirm the diagnosis of a cyst and, at the same time, drain the cyst fluid. Removing the fluid may reduce pressure and pain. Fluid may return, and more aspirations may be necessary. Having one or more cysts does not affect a woman’s risk of later developing breast cancer.
Epithelial hyperplasia: Epithelial hyperplasia (also known as proliferative breast disease) is an overgrowth of the cells that line either the ducts or the lobules. When hyperplasia involves the duct, it is called a ductual hyperplasia or duct epithelial hyperplasia. When it affects the lobule, it is referred to as lobular hyperplasia. Based on how it looks under the microscope, hyperplasia may be classified as usual type (without atypia) or atypical.
Usual hyperplasia indicates a very slight increase in a woman’s risk of developing breast cancer (1.5 - 2 times, the risk of women in the general population), while atypical hyperplasia indicates a moderate increase in risk (4 - 5 times). About 10% (1 in 10) of women with atypical ductal hyperplasia will develop invasive carcinoma within ten years of their biopsy. About 70% of biopsies done for benign breast conditions do not contain any hyperplasia. About 26% have usual hyperplasia and only 4% have atypical hyperplasia.
Epithelial hyperplasia is usually diagnosed by microscopic examination of a needle core biopsy or surgical biopsy.
A diagnosis of hyperplasia, particularly atypical hyperplasia, usually results in closer clinical follow-up (more frequent breast physical examinations and a particularly conscientious effort to get yearly mammograms) than that recommended for the general population. This is because having hyperplasia increases the chance of developing a breast cancer in the future.
Adenosis: Adenosis is a common finding in biopsies of women with fibrocystic changes. Adenosis refers to enlargement of breast lobules, which contain more glands than usual. If many enlarged lobules are found near one another, this collection of lobules with adenosis may be large enough to be felt. There are several names for this condition, including aggregate adenosis, tumoral adenosis or adenosis tumor. It is important to realize that even though this term contains the word "tumor," this condition is completely benign and is not a cancer. Sclerosing adenosis is a special type of adenosis in which there is distortion of the enlarged lobules by scar-like fibrous tissue.
When areas of adenosis and sclerosisng adenosis are large enough to be felt, it may be difficult for the doctor doing the breast physical exam to distinguish these lumps from a breast cancer. Calcifications (deposits of mineral material) may form in adenosis, in sclerosing adenosis, and in cancers, further confusing the situation.
Fine needle aspiration biopsy of adenosis can usually show whether the lump is benign. A core needle biopsy can usually identify the mass as adenosis, but a surgical biopsy is needed in some cases to be sure cancer is not present.
Some studies have found that women with adenosis have about the same (slightly increased) risk of developing breast cancer as do women with usual hyperplasa (about 1.5 – 2 times the risk of the general population).
Treating symptoms of fibrocystic change
Although researchers have made considerable progress in recognizing types of fibrocystic change that increase breast cancer risk, there has been much less progress toward understanding why this condition causes symptoms in some women. And progress in relieving these symptoms has been equally slow.
For rare women with painful cysts, draining the fluid by FNA can help relieve symptoms. Many other women without any large cysts have breast pain and tenderness.
Some women report that their breast symptoms improve if they avoid caffeine and other methylxanthines, the stimulants found in coffee, tea, chocolate, and many soft drinks. But scientifically conducted studies did not find those stimulants to have a significant impact on symptoms. Still, many women and their doctors feel that avoiding these foods and drinks for a couple of months is worth trying.
Because breast swelling toward the end of the menstrual cycle is painful to some women, some doctors have recommended that women reduce salt intake or take diuretics (drugs to remove salt and fluid from the body). But scientific studies find diuretics to be no better than placebo pills.
Several vitamin supplements have been considered, but none are proven to be of any use and some have dangerous side effects if taken in large doses.
Steroid hormones, such as those in oral contraceptives have been tried, but had no significant benefit.
Two drugs available by prescription only, bromocriptine and danazol, are used to treat women with severe symptoms. Both drugs work by affecting hormone metabolism. Both are expensive and have potentially serious side effects, but do help some women.
Fibroadenoma
Fibroadenomas are benign tumors made up of both glandular breast tissue and stromal (fibroconnective) tissue. They are most common in young women in their twenties and thirties, although they may occur at any age. African-American women are affected more often than women of other racial or ethnic groups. Some fibroadenomas are too small to feel and can be seen only under the microscope. At the other extreme, some are several inches across. They tend to be round and have borders that are distinct from the surrounding breast tissue, so they often feel like a marble within the breast. Some women have only one fibroadenoma, but others have several or many. Fibroadenoma can be easily diagnosed by fine needle aspiration or needle core biopsy.
Many doctors recommend surgically removing fibroadenomas, especially if they continue to grow or if they cause distortion of the breast ‘s shape. Sometimes (especially in middle aged or elderly women) these tumors will stop growing or even shrink on their own, without any treatment. In this case, as long as the doctors are confident the masses are really fibroadenomas and not breast cancer, surgery to remove them may not be necessary. This approach is particularly appropriate for women with multiple fibroadenomas that are not growing. In such cases, removing them all might require removing a significant amount of nearby normal breast tissue, causing scarring that would distort the shape and texture of the breast as well as making future physical examination and mammography more difficult to interpret. But, it is important that women whose fibroadenomas are not removed have a breast physical exam at regular intervals to make sure the mass does not continue to grow. Sometimes one or more new fibroadenomas will grow after one is removed surgically. This simply means that another fibroadenoma has formed and not that the old one has returned.
Phyllodes tumors
Phyllodes (also spelled phylloides) tumors are a rare type of breast tumor that, like a fibroadenoma, contains two types of tissue -- stroma (connective tissue) of the breast and glandular breast tissue. In contrast, carcinomas (the usual type of breast cancer) develop in the ducts or lobules of the breast’s glandular tissue. The difference between phyllodes tumors and fibroadenomas is that there is an "overgrowth" of the fibro-connective tissue portion of the tumor in the former. The cells that make up the fibro-connective tissue portion can be abnormal appearing under the microscope. Depending on their appearance under the microscope, phyllodes tumors may be classified as benign, malignant, or of uncertain malignant potential.
Phyllodes tumors are usually benign but on very rare occasions may be malignant, rarely having the potential to metastasize (spread). In the past, both benign and malignant phyllodes tumors were referred to as cystosarcoma phyllodes. Benign phyllodes tumors are successfully treated by removing the mass and a 2 cm (about 1 inch) margin of normal breast tissue. A malignant phyllodes tumor is treated by removing it along with a wide margin of normal tissue, or by mastectomy if necessary. Malignant phyllodes tumors do not respond to hormonal therapy and are less likely than most breast cancers to respond to chemotherapy or radiation therapy.
Intraductal papilloma
Intraductal papillomas are wartlike growths of gland tissue and fibrovascular tissue (fibrous tissue and blood vessels). Papillomas often involve the large milk ducts near the nipple. These result in a bloody nipple discharge. Papillomas may also be found in small ducts in areas of the breast distant from the nipple, where they are often multiple and commonly associated with epithelial hyperplasia. Although papillomas may be suspected by microscopic examination of a nipple discharge, this test is more often inconclusive and many doctors do not feel it is useful. If the papilloma is large enough to be felt, a needle biopsy can be done. The usual treatment is to remove the papilloma and a segment of the duct it is found in, usually through an incision at the edge of the areola (the pigmented zone of the surrounding the nipple).
Granular cell tumor
Granular cell tumors occur rarely in the breast. Most are found in the skin or the mouth, although they are uncommon even in those locations. They are almost always benign. Granular cell tumors are more common among African-American women than among other racial or ethnic groups.
Most granular cell tumors of the breast can be felt as a movable, firm lump. They are usually about ½ to 1 inch across. Their firmness may raise the possibility of cancer, but a fine needle or core needle biopsy can distinguish them from cancers.
This tumor should be surgically removed together with a margin of normal breast tissue. This treatment is curative. Granular cell tumors are unrelated to a woman’s risk of later developing breast cancer.
Fat necrosis
Fat necrosis occurs when an area of the fatty breast tissue becomes damaged. This is usually the result of injury to the breast. However, it can occur following surgery or radiation therapy. As a result of the body attempting to repair the damaged tissue, the area becomes replaced by firm scar tissue. Because most breast cancers are also firm, areas of fat necrosis with scarring can be difficult to distinguish from cancers by a breast physical exam. In these cases, the issue is usually resolved by a needle biopsy, although surgical excision is sometimes needed to be certain.
Some areas of fat necrosis can have a different response to injury. Instead of scar tissue forming, the fat cells die and release their contents, forming a sac-like collection of greasy fluid called an oil cyst. Oil cysts can be diagnosed by fine needle aspiration, which also serves as a treatment.
Mastitis
Mastitis is an infection that most often affects women who are breast-feeding. Cracking of the skin around the nipple allows bacteria from the skin surface to enter the breast duct where they grow and attract inflammatory cells. The inflammatory cells release substances that fight the infection, but also cause tissue swelling and increased blood flow. These changes cause the surrounding area to be painful and the overlying breast skin to be red and warm to the touch. This condition is treated with antibiotics. Some cases of mastitis lead to a breast abscess or collection of pus (inflammatory cells and fluid). Abscesses are treated by surgically draining the pus.
Duct Ectasia
Duct ectasia is a common condition that tends to affect women in their 40s and 50s. The most common symptom is a green or black, often thick, sticky discharge. The nipple and the surrounding breast tissue may be tender and red. Sometimes formation of scar tissue around the abnormal duct leads to a hard lump that may be confused with cancer. This condition sometimes improves without any treatment, or with warm compresses and antibiotics. If the symptoms persist, the abnormal duct is surgically removed through an incision at the border of the areola.
REFERENCES
Harris JR, Hellman S, Henderson IC, Kinne DW. Breast Diseases. Philadelphia: JB Lippincott; 1991.
Marchant D. Breast Disease. Philadelphia: Saunders; 1997.
MAMMOGRAM REPORTS (BIRADS)
The American College of Radiology (ACR) has developed a standardized way of describing mammographic findings and their significance and indicating the result by assigning a code (numbered 0 through 5). This system is called the Breast Imaging Reporting and Data System (BIRADS). Having a standard way of reporting mammography results allows doctors to use a consistent language and ensures better follow up on suspicious findings.
Category 0:Assessment is incomplete and additional imaging evaluation is needed.
A possible abnormality may not be completely seen or defined and will need additional evaluation including the use of spot compression, magnification views, special mammographic views, or ultrasound.
Category 1: Negative
In this case, there is no significant abnormality to report. The breasts are symmetrical without masses, architectural distortion or suspicious calcifications.
Category 2: Benign (non-cancerous) Finding
This is also a negative mammogram, but the reporting physician chooses to describe a finding known to be benign such as benign calcifications, intramammary lymph nodes and calcified fibroadenomas. This insures that other individuals viewing the mammogram will not misinterpret a benign finding as suspicious, and documents the finding to use in future mammogram assessments.
Category 3: Probably Benign Finding - Follow-up in a short time frame is suggested
The findings placed in this category should have a very high probability of being benign. The findings are not expected to change over a period of follow-up. Since it is not proven benign, it is helpful to see if an area of concern changes over time. Follow up with repeat imaging is usually done every 6 months for a year and then every year for 2 years. This will help avoid unnecessary biopsies but allow for findings that are cancers to be detected within a short period of time.
Category 4: Suspicious Abnormality-Biopsy Should Be Considered
Findings do not definitely look like cancer, but have a substantial probability of being malignant. The radiologist has sufficient concern to recommend a biopsy.
Category 5: Highly Suggestive of Malignancy - Appropriate Action Should Be Taken
The findings are characteristic of cancers and have a high probability of malignancy. Biopsy is very strongly recommended.
Ductogram (Galactogram)
A ductogram is a test that is sometimes helpful in determining the cause of a nipple discharge. This is a type of x-ray test in which a fine plastic tube is placed into the opening of the duct onto the nipple. A small amount of contrast medium is injected, which outlines the shape of the duct on an x-ray image and will show whether there is a mass inside the duct.
Breast Ultrasound
Ultrasound, also known as sonography, is an imaging method in which high-frequency sound waves are used to outline a part of the body. High-frequency sound waves are transmitted through the area of the body being studied. The sound wave echoes are picked up and translated by a computer into an image that is displayed on a computer screen. No radiation exposure occurs during this test.
Breast ultrasound is sometimes used to evaluate breast abnormalities that are found at screening or diagnostic mammography or on physical exam. Breast ultrasound is not routinely used for screening. Some studies have suggested that ultrasound be considered in screening of women with dense breast tissue (which is difficult to evaluate by routine mammography). But, use of ultrasound instead of mammography is not recommended because small calcium deposits, which are one of the earliest signs of cancer, are not visible by ultrasound. Ultrasound is useful for evaluation of some breast masses and is the only way to tell if a cyst is present without placing a needle into it to aspirate fluid. Cysts cannot be accurately diagnosed on physical exam alone. Breast ultrasound may also be used to help doctors precisely guide a biopsy needle into some breast lesions.
Imaging-guided Breast Biopsy
Mammography cannot prove that an area seen on the films is due to a cancer. If mammography raises a significant suspicion of cancer, a biopsy (a sample of cells or tissue removed for examination under the microscope by a pathologist) is needed to tell if the suspicious area is indeed cancer.
For years, excisional surgical biopsy was the only option for this purpose. The surgeon doing the biopsy makes an incision in the skin of the breast and removes the entire lesion (abnormal area) together with a narrow zone of normal tissue. Today many suspicious breast abnormalities can be diagnosed without surgery by using needle biopsy. There are two types of needle biopsies -- fine needle aspiration biopsy (FNAB) and core needle biopsy (CNB). FNAB uses a very thin needle to remove fluid and tiny fragments of tissue. CNB uses a slightly larger needle to remove a cylindrical piece of tissue about 1/16 inch in diameter and ½ inch long. If the breast mass is large enough to feel, the physician can directly guide placement of the biopsy needle by touch. But, even if an abnormality is too small to be felt, FNAB or CNB can still be done using breast imaging methods such as ultrasound and stereotactic mammography to guide the needle into the lesion.
During an ultrasound examination, the physician can view the needle on a screen as it moves toward and into the mass.
Stereotactic needle biopsy is a method that is useful in some cases in which calcifications or a mass can be seen on mammogram but cannot be located by touch. Based on mammograms taken from two angles, computerized equipment maps the precise location of the mass or calcifications. A small electric motor controlled by the computer guides the placement of the needle for CNB or, less often, FNAB.
Wire localization is a procedure used to guide a surgical (excisional) breast biopsy of a small lump that is difficult to locate by touch or of areas that look suspicious on the x-ray (due to calcifications, for example) but do not have a distinct lump. After numbing the area with local anesthetic, a hollow needle, thinner than that used for drawing blood, is placed into the breast and x-ray pictures are taken to guide the needle to the suspicious area. A thin wire is inserted through the center of the needle. A small hook at the end of the wire keeps it in place. The hollow needle is then removed, and the surgeon uses the wire as a guide to locate the abnormal area to be removed.
The Mammotome and ABBI are two instruments used to obtain stereotactic breast biopsies. One potential disadvantage of fine needle and core biopsy methods for biopsy of abnormalities found by mammography (such as microcalcifications) is that they remove only a small sample of tissue from the abnormality. If the biopsy finds cancer, it can be assumed to be accurate. But, if no cancer is found, there may be some uncertainty as to whether the needle point missed the target. Until recently, an excisional biopsy with wire localization was the only way to remove all or most of a non-palpable (seen on mammography but cannot be felt) area of abnormal tissue containing microcalcifications. During the past few years, two new devices have been invented that can be guided by stereotactic methods and can remove more tissue than a core biopsy. The Mammotome, also known as vacuum-assisted biopsy, uses suction to draw tissue into an opening in the side of a cylinder inserted into the breast tissue. A rotating knife then cuts the tissue samples from the rest of the breast. This method usually removes about twice as much tissue as core biopsies. The ABBI method (short for Advanced Breast Biopsy Instrument) uses a rotating circular knife, and a thin wire heated by electrical current to remove a large cylinder of tissue containing the abnormality. The amount of tissue sampled with the ABBI is usually much greater than with the Mammotome. Both the Mammotome and ABBI instruments have been recently approved by the US Food and Drug Administration (FDA) for use in diagnosis of breast abnormalities. But, breast specialists still disagree about when each of these instruments should be used for diagnosis of non-palpable abnormalities, and whether some should be used at all. There is even more disagreement about whether the ABBI should be used in some situations to replace an excisional biopsy with wire localization as a lumpectomy procedure.
The accuracy rates for FNAB, CNB, Mammotome, ABBI, and surgical biopsy are similar. The accuracy of each method depends on the experience of the doctor with that method, but this is especially true with methods that remove smaller amounts of tissue (FNA and core needle biopsy) and, therefore, require more accurate placement of the needle. Each type of biopsy has distinct advantages and disadvantages. The choice of which to use depends on each patient's situation and needs. Some of the factors to consider include how suspicious the lesion appears, how large it is, where in the breast it is located, how many lesions are present, other medical problems the patient may have, and her personal preferences. Women are encouraged to discuss the advantages and disadvantages of different biopsy types with their doctors.
New and Experimental Breast Imaging Methods
Mammography is an excellent way to find most breast cancers at their earliest and most curable stage. However, mammography does not detect all breast cancers. Tremendous research efforts are ongoing in the field of breast imaging in order to increase the number of cancers found at imaging before they are felt by the patient or her physician, to find cancers even smaller than those detected currently by mammography, and to improve the accuracy of breast imaging in distinguishing benign breast conditions from breast cancers. New methods being studied include magnetic resonance imaging (MRI), digital mammography, nuclear medicine studies, and computer aided diagnosis.
Magnetic resonance imaging (MRI) uses magnetization and radio waves, instead of x-rays, to produce very detailed, cross-sectional images. The most useful MRI examinations for breast imaging use a contrast material (Gadolinium DTPA) that is injected into a small vein in the arm before or during the examination. This contrast material improves the capability of MRI to clearly show details of breast tissue. It was hoped that MRI would be equal or better than mammography in diagnosing breast cancer. Although MRI can detect some abnormalities not seen on the mammogram, it is less accurate than routine mammography in determining which of the abnormal areas are cancer and which are not. Studies are underway to continue refining technology for breast MRI, and to better define the role of currently available instruments. Some radiologists have suggested that MRI might be useful in women whose routine mammograms show abnormal areas of uncertain significance. But, most radiologists feel that until the accuracy of MRI improves, it will remain an experimental technique that has limited use. As noted earlier, MRI is very useful in detecting rupture of breast implants. Just as x-ray mammography uses dedicated equipment (x-ray machines designed especially for mammography), breast MRI also requires special equipment. Higher quality images are produced by dedicated breast MRI equipment than by equipment designed for head, chest, or abdominal MRI scanning. However, most hospitals and imaging centers do not have dedicated breast MRI equipment available.
Digital mammography is similar to standard mammography in that x-rays are used to produce an image of the breast. The differences are in the way the image is recorded, viewed by the doctor, and stored. Standard mammography images are recorded on large sheets of photographic film. Digital images are captured electronically and viewed on a computer monitor (like a television screen). They are stored on a computer and their magnification, brightness, or contrast can be changed after the exam is done to help the doctor more clearly see certain areas. Digital images can be transmitted over phone lines to another site for remote consultation with breast specialists. Digital mammography is commonly used in stereotactic imaging to guide breast biopsy because it is rapid and reliable. Initial studies have demonstrated that digital mammography is at least as accurate as standard images; additional work with this technique may show digital mammography to be superior. Early in 2000, the FDA approved for the first time a digital mammography system that can now be used for routine breast cancer screening. While many facilities providing mammography services do not currently offer the digital option, it is expected to become more widely available in time.
Nuclear medicine involves the injection into the body of very tiny amounts of a radioactive substance linked with a second substance that collects in the targeted organ. For breasts, a compound known as technetium sestamibi has been evaluated to help diagnose breast cancer. This test is manufactured by DuPont under the trade name "Miraluma". The procedure involves the injection of a small amount of radioactive substance into an arm vein followed by imaging with a commonly available nuclear medicine camera that records where in the breasts radiation has accumulated. This test cannot distinguish cancer from non-cancerous lesions as accurately as routine mammography. Some radiologists believe it is sometimes useful in evaluating abnormalities of uncertain significance found by regular mammograms. However, studies of the test have yielded varying results. The consensus is that this test is far less sensitive than mammography, especially when the tumor is still small and most likely to be curable. For these reasons, the exact role of this test remains uncertain. Research is in progress, aiming to improve the technology and evaluate its use in specific situations such as dense breasts of younger women.
Positron emission tomography, also known as PET scanning, is a newer type of nuclear medicine study. As in the sestamibi test described above, a tiny amount of radioactive substance is injected into an arm vein. This substance gives off a small amount of radiation that is detected by a special PET scanner to form an image. The most commonly used substance is fluorodeoxyglucose (FDG) which is metabolized (used by cells) in the body like sugar. It goes where the tissue is most active, especially highlighting cancerous tissue. Unlike most other imaging tests that are based on changes tumors cause in the body's structure, PET scanning depends on changes in tissue metabolism. PET is being used to detect metastatic disease (cancer spread) and has been successful in that role. It is not currently used for primary breast cancer detection because it does not reliably detect tumors smaller than 1 cm, but research to improve the accuracy of this test is in progress.
Computer-aided diagnosis refers to use of computers that help doctors recognize abnormal areas on a mammogram. These instruments convert a mammographic image into a digital signal that is analyzed by the computer. The computer then displays the image on a video screen, with markers pointing to areas it "thinks" the radiologist should check especially closely. The US Food and Drug Administration (FDA) for use in reviewing mammograms have approved one such device, the M 1000 ImageChecker. Preliminary tests have found that it can find some cancers that doctors might have otherwise missed. But, doctors still disagree about how many cancers the device will pick up. Some doctors feel that the device is not as effective as simply having another radiologist review the films, and others are concerned that the device may lead to unnecessary biopsies by falsely identifying benign abnormalities as being suspicious for cancer. Most breast specialists are encouraged by recent progress in computer-aided diagnosis, and look forward to additional technical refinements and studies that help to clarify their role in breast cancer detection.
Mammography With Special Circumstances
Mammography after Breast Conserving Treatment (BCT):
Removal of the entire breast, known as mastectomy, is one way of treating breast cancers. Most breast cancers can be just as effectively treated by breast conserving treatment (BCT) without removing the entire breast. Lumpectomy is a type of BCT and refers to removal of a cancerous lump and a narrow safety zone or margin of benign breast tissue. Lumpectomy is almost always combined with radiation treatment. Chemotherapy is often given. All of these are components of BCT.
A woman who has had BCT will need to continue having mammograms of the affected breast and of the unaffected side. Most radiologists recommend that patients have a mammogram of the treated breast six months after the completion of radiation treatment. Radiation and chemotherapy both cause changes in the skin and breast tissues that show up on the mammogram and make the examination more difficult to interpret. These changes are expected to be at a maximum at six months after the radiation is completed; the mammogram at this time establishes a new baseline for the affected breast for that woman. Future mammograms will be compared to this exam to follow healing and check for recurrence. The next examination is then six months later when the woman is due for her yearly mammogram of both breasts. Experts differ on the best follow-up plan from this point on. Some prefer mammography of the treated breast every six months for 2-3 years; others suggest that annual mammograms are adequate. Each woman should consult her doctor for the plan that is best for her.
Mammography after breast reconstruction:
Women who have undergone total, modified radical, or radical mastectomy for breast cancer need no further routine mammography of the affected side (or sides, if both breasts are removed). Mammography is continued for the unaffected breast at standard one-year intervals. This is very important, since women who have had one breast cancer are at higher risk of developing a new cancer of the other breast. One type of mastectomy that does require follow-up mammography is the subcutaneous mastectomy. In this operation, the woman retains her natural nipples and the tissue just under the skin; enough tissue is left behind to require yearly screening mammography in these patients. Any woman who is unclear of the type of mastectomy she has had should ask her physician.
Mammography is not routinely required for a breast removed by total, modified radical, or radical mastectomy and reconstructed with silicone gel or saline implants. If the patient has had subcutaneous mastectomy (discussed above), annual imaging is still needed.
After mastectomy, some women choose to have reconstruction with tissue from their own body, most often the abdomen (stomach) area. This type of reconstruction is called a TRAM flap reconstruction, which stands for Transverse Rectus Abdominus Myocutaneous flap. A patient who has had complete (not subcutaneous) mastectomy followed by TRAM flap reconstruction needs no further screening mammography on the affected side. If there is an area of the TRAM flap that is of concern on the physical examination, diagnostic mammography may occasionally be obtained. Further imaging with ultrasound or MRI may also be helpful.
Mammography after Breast Augmentation (enlargement) with Implants:
Women who have implants are a special challenge at mammography. The x-rays used for imaging the breasts cannot penetrate silicone or saline implants well enough to image the overlying or underlying breast tissue. Therefore, some breast tissue will not be seen on the mammogram, as it will be covered up by the implant. In order to visualize as much breast tissue as possible, women with implants undergo four additional films as well as the four standard images taken during screening mammography. In these additional x-ray pictures, called implant displacement (ID) views, the implant is pushed back against the chest wall and the breast is pulled forward over it. This allows better imaging of the forward most part of each breast. The implant displacement views are not as successful in women who have contractures (formation of hard scar tissue around the implants). They are easiest to obtain in women whose implants are placed underneath (behind) the chest muscle.
Although implant rupture can sometimes be diagnosed on the mammogram, often the ruptured implant will appear normal at mammography. Mammography does not cause implant rupture. Magnetic resonance imaging (MRI) is extremely accurate in detecting implant rupture. MRI is the imaging method of choice to evaluate the implant itself while mammography is still the best test for evaluating breast tissue. See the section on New and Experimental Breast Imaging Methods for more information on MRI.
The guidelines for screening mammography of women with implants are the same as for women without them. The number of pictures taken for each examination, however, is greater.
Regulation of Mammography
Mammography in the United States is highly regulated. Although mammography using dedicated machines has improved since its introduction since 1969, studies in the mid-1980s showed that quality varied greatly from place to place. In an attempt to educate those working with mammography, improve quality, and lower dose, the American College of Radiology (ACR) started the first national Mammography Accreditation Program (MAP) in 1986. This voluntary program raised standards nationwide and led to better mammography at those sites participating in the program. In 1992, Congress enacted a law to apply similar standards at all mammography facilities. The standards are no longer voluntary and today, the US Food and Drug Administration (FDA) must certify each mammography facility (except those of the Department of Veterans Affairs). In order to be certified, each mammography machine has to be accredited by an acceptable accreditation body: either the American College of Radiology (ACR) or the States of Arkansas, California, or Iowa. The accreditation body reviews the facility's equipment, the qualifications of the personnel involved in mammography, and the way each practice is run. The personnel who have to meet strict standards include the radiologists (the physicians who interpret the mammograms), the radiologic mammography technologists (the individuals who actually position women for the exam and take the mammogram pictures) and the medical physicists (professionals who specialize in medical equipment and image production). Each facility must submit typical images (x-rays) which are reviewed for quality and information on radiation dose, which is required to be very low. If the accreditation body finds that the facility meets all of the appropriate standards, the FDA gives its certification. These standards are outlined in the Mammography Quality Standards Act (MQSA), which was passed by Congress and has been in effect since 1994. It is unlawful to perform mammography in the United States without an FDA certificate.
The FDA maintains a listing by state and zip code of all mammography facilities certified by FDA. This list is available at the FDA's website: www.fda.gov/cdrh/faclist.html.
Mammography clinics are now required to notify women in writing about the results of their mammograms. The Mammography Quality Standards Act, under Food and Drug Administration regulation, was recently changed in response to reports that some women may not have learned soon enough they had suspicious mammograms. Mammogram clinics are continuing to report mammogram results to the woman's doctor, who is responsible for ordering additional tests or treatments. Many clinics already voluntarily send a copy to women. The new amendment to the regulation requires clinics to mail women a separate, easy-to-understand report of their mammogram results within 30 days -- sooner if the mammogram results suggest cancer is present -- so that the woman knows the results even if her doctor has not yet called to inform her.
Patient Preparation
Mammography requires little preparation by the patient. If a woman has had mammograms at another facility, she should make every attempt to obtain those mammograms so that they are available to the radiologist at the time of the current examination. On the day of the examination, the woman should not wear deodorant; this can interfere with the mammogram by appearing on the x-ray film as calcium spots. Women who experience breast tenderness the week prior to their periods should avoid mammography during this time. The optimal time for mammography in these patients is one week after their period. Any breast symptoms or problems that the woman is experiencing should be described to the technologist performing the examination. A woman should also be prepared to discuss with the mammography technologist any pertinent history: prior surgeries, hormone use, family or personal history of breast cancer. The woman should also discuss any new findings or problems in her breasts with her clinician prior to mammography.
References
American Cancer Society. Cancer Facts and Figures 1998. Atlanta, GA: American Cancer Society, 1998.
Foster R, Monticciolo DL. Follow-up after breast-conserving surgery. In Surgery of the Breast: Principles and Art, edited by Spear SL. Lippincott-Raven, Philadelphia, Pa. 1997
Henderson IC. Breast cancer. In Clinical Oncology, edited by Murphy GP, Lawrence W, and Lenhard, RE, Jr., Atlanta: The American Cancer Society, 1996, 198-219.
Kopans DB. Breast Imaging. JB Lippincott. Philadelphia, Pa. Second Edition, 1998.
Mammography Matters. Food and Drug Administration, Center for Devices and Radiological Health. Rockville, MD. 1998.
Story posted Thursday, 01-Oct-98 08:49:17 - Online Athens
New procedure may reduce lymph node removal in breast cancer surgery
Associated Press
BOSTON - A new procedure may allow surgeons to reduce dramatically the number of lymph nodes they remove during breast cancer surgery, sparing women some of the pain and possible complications.
During operations to remove breast cancer, doctors also routinely take out the lymph nodes around the armpit in case the cancer has spread to these glands.
Removing the nodes may improve the chances of survival. The presence of cancer there also tells doctors how aggressively to use cancer drugs.
Just as doctors have learned that they can often safely remove just the lump rather than the whole cancerous breast, they are now experimenting with the idea that not all the lymph nodes need to come out, either.
In a study in today's issue of the New England Journal of Medicine, doctors from the University of Vermont provided encouraging evidence that a far less drastic procedure may work.
The procedure involves injecting radioactive material around the tumor and then removing only the nodes that eventually absorb it.
"It's quick and easy to precisely locate the node before ever making an incision. That's the key advantage," said Dr. David Krag, who helped pioneer the technique.
Krag trained 11 other surgeons to use the method. They reported the results of testing on 443 patients.
Ducts in the breast carry fluid to the lymph nodes under the arms. Each area of the breast drains to a different node.
The doctors inject technetium-99 into the breast around the tumor. Eventually, about 1 percent of this radioactive material makes its way to the lymph nodes. The doctors use a handheld gamma ray counter to find which ones absorbed it.
Doctors then remove only these so-called sentinel nodes and see if they are cancerous.
In this study, however, they also took out all the remaining lymph nodes so they could see how accurate the procedure had been.
They found that if the gamma ray counter picked up a signal, the procedure was 97 percent accurate at pinpointing all the cancerous nodes. However, the procedure missed cancerous nodes in 13 of the 114 women with spreading cancer.
In an accompanying analysis, Dr. V. Suzanne Klimberg of the University of Arkansas and others said the chance of missing cancerous nodes is the main drawback.
Krag said that by doubling the dose of radioactive material, it may be possible to lower the number of missed cases substantially.
Doctors will test this idea in a large study, sponsored by the National Cancer Institute, that will get under way in about three months. The sentinel node procedure will be tested against standard lymph node removal in about 4,000 women.
The primary advantage of the new approach is that it removes about 50 times less tissue than standard surgery. Krag said doctors take out one to three grams of tissue instead of the usual 100 to 150 grams.
This means the technique can be done under local rather than general anesthesia, and recovery is much faster. Patients are also likely to avoid many of the possible complications, such as arm swelling, limited shoulder motion and lingering pain from damaged nerves.
Krag said some surgeons are already using the procedure, but he recommends limiting it for now to medical studies.
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