Types of Abnormal Screening Findings
Typically, a clinical breast exam or mammogram will show no sign of disease. However, for some women, the test results will prove to be abnormal, and they will need to have additional tests to determine whether they have cancer. Which tests are performed depends on a number of factors, such as the type of abnormality found and the age of the woman. Usually the follow-up tests begin with the least invasive methods, such as an ultrasound or second mammogram, and progress, if necessary, to the more invasive methods, such as a needle or surgical biopsy. A biopsy should spare the tissue, removing just enough tissue to make a diagnosis without being unnecessarily invasive. A woman should not rush from one abnormal screening mammogram or clinical breast exam to a major invasive surgical procedure or to treatment for breast cancer. Following the series of tests outlined below may help avoid unnecessary procedures.
From a Clinical Breast Exam
A lump called a palpable mass is the most common abnormal finding from a clinical breast exam. The first determination that must be made is whether the mass is solid or fluid-filled. Most likely, if it is fluid-filled, the mass is a cyst. Simple fluid-filled cysts are not cancerous and can be left untreated in many cases. However, complex cysts contain both solid tissue and fluid and may need additional examination to assure they are not cancerous. Solid masses, on the other hand, are potentially cancerous.
For Individuals Age 30 and Older
The general approach to follow up a palpable mass involves further examination of the mass with a diagnostic mammogram, ultrasound, or needle biopsy. Mammography with or without an ultrasound is often the first choice. However, a person with a mass that is likely not cancerous may choose to begin follow-up with a needle biopsy. Instead of an initial needle biopsy, most individuals with a palpable mass begin follow-up tests with a mammogram and/or ultrasound of the mass. This imaging may help avoid a needle biopsy by identifying a mass as a simple cyst, complex cyst, or a suspicious mass that could be cancerous.
A needle biopsy is the insertion of a thin, hollow needle into a breast mass to ascertain if fluid can be drawn out (aspirated). If fluid can be aspirated, this indicates that the mass is a cyst. If the cyst is completely reduced after being aspirated and does not return after 2-3 months, then no further treatment is required. If the mass is not completely reduced after being aspirated or if it later returns, then additional steps are necessary to rule out cancer, including another needle biopsy, an ultrasound examination, or surgical removal of the mass.
If fluid is not aspirated during the initial needle biopsy, this is an indication that the mass is solid, and an examination of the tissue removed during the needle biopsy will determine the next step. If the mass is found to be a fibroadenoma, then the woman has a choice to make: Have it removed or have it closely monitored. Removal involves surgery, but can determine definitively whether or not there is any cancer present.
If the initial needle biopsy results are unclear, then the mass will be examined with mammography and/or ultrasound, followed by either another needle biopsy or a surgical biopsy. However, if the initial needle biopsy reveals cancer, then treatment should begin at once.
For Individuals Under Age 30
In this age group, the follow-up is slightly different because most individuals with a palpable mass have a very low rate of breast cancer. Follow-up of a palpable mass usually begins with observing the mass for a duration of 1-2 menstrual cycles (in women) to see if it persists or disappears. During this follow-up period, clinical breast exams should not be performed in the week before or during a woman's menstrual period because cysts can become enlarged during menstruation. If the mass remains after the observation period, then an ultrasound or needle biopsy will be performed. If a woman has a strong family history of cancer (e.g., two or more immediate family members with cancer), there is increased risk of breast cancer, and an ultrasound or needle biopsy may be performed without waiting.
Other Abnormal Findings from a Clinical Breast Exam
In addition to a palpable mass, other potentially abnormal findings during a clinical breast exam include thickening within the breast, changes to the skin, and nipple discharge. Any of these abnormal findings require a follow-up to assure that they are not signs of cancer.
Abnormal Findings from a Mammogram
Nonpalpable lesions are tissue abnormalities that generally are either too small to be detected during a clinical breast exam or are spread out in such a way that there is no lump even if the mass is large. Nonpalpable lesions are typically found by mammogram.
First, the radiologist compares the mammogram with previous (or baseline) abnormal mammograms. Next, the radiologist will perform a diagnostic mammogram, focusing on the area where there appears to be abnormal tissue. An ultrasound of the area may also be performed.
The next step will be determined based upon the findings from the diagnostic mammogram and ultrasound. If the lesion is clearly not cancer (e.g., a simple cyst), there is no further follow-up necessary. If the lesion appears likely to be benign (e.g., a fibroadenoma), a repeat mammogram at 6 months and follow up at the physician's discretion is required.
A suspicious lesion can be cancerous; therefore, the next step is to perform a biopsy of the lesion, using stereotactic fine needle aspiration or core needle biopsy (both will be discussed later in this protocol). If the biopsy findings do not agree with the mammogram findings, both procedures must be repeated. If the findings are in agreement, a diagnosis can be made. If the lesion is found to be cancerous, treatment should commence immediately. If the lesion is benign, a follow-up mammogram should be performed within a year. If the follow-up mammogram reveals nothing abnormal, then a woman can return to her normal schedule of mammograms and clinical breast exams. If a lesion is a particular type of benign breast disease (e.g., atypical hyperplasia), the lesion should be excised and examined for the presence of cancer. If cancer is found, treatment should commence immediately. If no cancer is found, then a woman can return to her normal screening schedule.