Breast Lumps and Abnormal Mammograms
The vast majority of breast lumps and breast complaints are caused by benign breast disease, like cysts and fibroadenomas. All the same, your doctor takes breast lumps very seriously and will pursue further testing and evaluation to determine a cause.
Diagnosis
Breast lumps can present as lesions that can be felt (palpable) by the patient or doctor or as nonpalpable lesions detected with a mammogram.
The first step in the evaluation of breast lumps is a medical history and physical exam. This includes:
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the precise location of the lump
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how it was first detected (accidentally, by breast self-examination or during a clinical breast exam or mammogram)
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if and how long the patient has noted its presence
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whether there is any accompanying nipple discharge
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whether the lump has changed in size
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whether the lump waxes and wanes in size at particular times in the menstrual cycle. Benign cysts may be more prominent premenstrually and regress in size during the follicular phase (just after menses).
Physicians should also ask about a past history of breast cancer or breast biopsy and a history of risk factors for breast cancer (e.g., age, family history of breast cancer, age of menarche, age at first pregnancy, age of menopause, alcohol use, and hormonal replacement therapy). Older age, history of breast cancer and family history in a first-degree relative all increase the risk of breast cancer.
Breast tissue in normal women is often lumpy, so the physical exam should concentrate on those factors that differentiate breast cancer from benign lesions. A number of "classic" characteristics of cancerous lesions include:
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a single lesion
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hard and immovable
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irregular borders
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greater than two centimeters in size
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can be painful, though usually are painless
Most women will need further testing like mammography, ultrasound, fine needle aspiration and core needle biopsy. The challenge is to be as sure as possible that the breast lump does not contain cancer while at the same time minimizing the invasiveness of the procedure.
Mammography is the process of using low-energy X-rays to screen the breast for characteristic masses and microcalcifications. Diagnostic mammography is recommended as part of the evaluation of any woman age 35 or older who has a breast mass. However, mammography usually cannot determine whether a lump is benign (not cancerous). In addition, mammography misses 10 to 20 percent of clinically palpable breast cancers. Thus, a negative mammogram should not stop further investigation if a suspicious lump is felt on clinical examination.
Ultrasonography can determine whether a breast mass is a simple or complex cyst or a solid tumor. It is most useful in the following circumstances:
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in women under age 35
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when a mass detected on screening mammography cannot be felt
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when the patient declines aspiration of a mass
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when the mass is too small or deep for aspiration
Fine needle aspiration biopsy, or FNAB, is easy to perform, requires no advanced preparation and can be carried out in the office. To aspirate a suspected cyst, the mass is stabilized between the fingers of one hand and a needle is inserted with the other hand. Local anesthesia may be used but is not always required. FNAB is especially valuable in evaluating cystic breast lesions and can be therapeutic if all of the fluid is removed. There are three possible scenarios with FNAB:
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Fluid that is obtained and is not bloody does not need to be sent for analysis. The mass should disappear with the removal of fluid and the patient can be reassured and checked in a few weeks to ensure that the cyst has not reappeared; a recurrence suggests the need for surgical referral.
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Bloody fluid from patients with otherwise benign examinations should be sent for pathological analysis.
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When no fluid is obtained and the mass turns out to be solid, cells can be obtained by aspirating cells from the solid mass.
Core needle biopsy is different from FNAB; a larger needle is used with the former. Core needle biopsy is used most often for evaluating nonpalpable breast lumps in conjunction with either mammogram or ultrasound guidance.
Triple diagnosis includes a physical exam, mammography and skilled FNAB for diagnosing palpable breast lumps. Very few breast cancers are missed using triple diagnosis. The following scenarios occur with the triple diagnosis approach:
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Women in whom all three tests suggest benign disease receive a thorough physical exam every three to six months for one year to make sure the mass is stable or regresses.
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Women in whom all three tests suggest malignancy are referred for definitive therapy.
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Women in whom any one of the tests suggest malignancy will undergo excisional biopsy