TYPES OF ABNORMAL SCREENING FINDINGS
- From a Clinical Breast Exam
- Needle Biopsy
- Other Abnormal Findings from a Clinical Breast Exam
- Abnormal Findings from a Mammogram
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 ExamFor Individuals Age 30 and Older
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.Needle BiopsyFor Individuals Under Age 30
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.TYPES OF BIOPSIES
- Core Needle Biopsy
- Fine Needle Aspiration
- Excisional Biopsy
- Wire Localization for Nonpalpable Lesions
- Frozen Sections
- Excisional Biopsy as a Surgical Treatment
- Incisional Biopsy
Two general categories of biopsies are used to diagnose breast cancer. These are:
Core Needle Biopsy
- Needle biopsies, which include core needle biopsy and fine needle aspiration.
- Open biopsies, which include excisional biopsy (including wire localization) and incisional biopsy.
Core needle biopsy, or cutting needle biopsy, is a method of procuring tissue samples from the breast using a thin, hollow needle. Palpable lumps can be biopsied in a doctor's office using local anesthetic. Using the fingertips to isolate the lump, the doctor makes a small nick in the skin, inserts a needle, and removes a sample of the tissue from the suspicious area. A pathologist, who microscopically evaluates the breast tissue and/or lymph nodes removed during biopsy or surgery for cancer, then examines the tissue sample.
For nonpalpable areas that cannot be felt to be sampled, the procedure is more involved and will likely be performed in a hospital or outpatient clinic because of the need for special equipment to locate and accurately sample the correct area. An ultrasound or special three-dimensional mammography, called stereotactic mammography is used.
A core needle biopsy using stereotactic mammography entails first placing a woman on her stomach on a mammography table with the affected breast fitted through a hole in the table. The breast is compressed so that it will remain in place to record an accurate image. Calculations are made based on this image, and a biopsy device containing a needle automatically takes a number of tissue samples from the affected area in the breast. Multiple samples increase the chances of an accurate diagnosis. This procedure involves little pain because the device inserts and removes the needle very quickly.
A core needle biopsy using ultrasound entails a women lying on her back and the doctor holding an ultrasound transducer against the breast. The transducer makes an image of the area to be sampled, allowing the doctor to follow the needle as it enters the breast and reaches the abnormal area. The needle is then inserted by hand and a sample of tissue is removed.
The core needle biopsy provides several advantages. It supplies specific information about a tumor, such as whether it is in situ or invasive. It is accurate, quick, relatively inexpensive, only mildly uncomfortable, and does not involve surgery.
There are disadvantages to the core needle biopsy. The most important is that the core needle biopsy can produce false negative results. False negatives may occur if the needle misses the tumor and instead takes a sample of normal tissue. This can impact a woman's chances for long-term survival because the undiagnosed cancer may go untreated. Furthermore, the samples taken may not provide complete information about a tumor; a tumor may be diagnosed as being in situ instead of invasive. Taking multiple tissue samples can help limit this potential problem.Fine Needle Aspiration (FNA)
Fine needle aspiration (FNA), also known as fine needle biopsy, is a method of procuring cell samples using a very thin needle. Although FNA can be performed on both palpable lumps as well as nonpalpable areas found by mammogram, FNA is recommended only for use on palpable lumps. The key to an accurate diagnosis is the removal of an adequate number of cells from the suspicious area. With nonpalpable lesions, however, FNA can frequently remove insufficient samples of cells, especially compared to core needle biopsy.
For palpable lumps, FNA can be done in a doctor's office. During the procedure, the doctor will locate and isolate the lump with the fingertips, insert a very thin needle attached to a syringe, and draw out (or aspirate) a sample of cells. The needle is so thin that there is little pain, and no anesthetic is needed. The whole procedure takes only a few minutes. Then the sample cells will be sent to a doctor or a cytopathologist who specializes in examining individual cells for a diagnosis.
The advantages of FNA are that it is quick, relatively inexpensive, only mildly uncomfortable, and does not involve surgery. FNA is an excellent method of diagnosing cancer when it is performed on a palpable lump by an experienced doctor and is analyzed by an experienced cytopathologist.
There are several disadvantages to using the FNA procedure. FNA is not recommended for nonpalpable lesions. Even for palpable masses, FNA may not remove enough cells for the cytopathologist to be able to make an accurate diagnosis. In addition, false negatives occur in about 0-4% of FNA procedures performed on palpable lesions (Harris et al. 1997). As a result, a woman having an FNA may need to have a more definitive biopsy, such as a core needle or excisional biopsy, to ensure that the palpable lesion is not cancerous.
Another drawback of FNA is that while it can be used to determine if cells are cancerous, it cannot distinguish in situ cancers from invasive cancers. However, these two types of cancers are generally treated differently via surgery. Finally, FNA requires an experienced breast cytopathologist to accurately analyze the sample of cells, a type of physician that not all hospitals or medical centers will have on staff.Excisional Biopsy
An excisional biopsy is the most accurate method for diagnosing breast cancer. It is also referred to as "lumpectomy" or "partial mastectomy." An excisional biopsy is performed by a surgeon and is generally done under a local anesthetic, meaning that the area to be operated on is desensitized, but the patient remains awake. During the procedure, the surgeon makes an incision in the breast and removes the entire suspicious area and a small amount of surrounding normal tissue. Most women are able to have a biopsy and return home the same day.Wire Localization for Nonpalpable Lesions
A nonpalpable lesion is difficult to locate during an excisional biopsy. Therefore, a radiologist uses a mammography or ultrasound image for direction and a surgeon inserts a very thin wire into the breast as a guide to identify the breast tissue that requires removal. The surgeon then removes the abnormal tissue. This procedure is called wire localization or needle localization.
Once the nonpalpable mass is removed, the tissue is x-rayed immediately. This allows the surgeon and radiologist to match the suspicious areas on a woman's mammogram with those in the biopsy tissue. If the areas do not match, the surgeon has two options. One option is for the surgeon to make an additional attempt to remove the correct tissue. The other option is to wait and rebiopsy at another time when the area has been targeted a second time using the wire localization technique.Frozen Sections
Immediately after the tumor is removed from the breast, a frozen section is usually performed. This process entails freezing a portion of the biopsied tissue and then quickly cutting a thin slice for the pathologist to analyze under the microscope. In the past, if a biopsy came back as positive for cancer, surgical treatment was performed immediately. Currently, biopsies are prior to and separate from the definitive surgery. However, immediate results using frozen sections can help alleviate a woman's anxiety.
A high percentage of false negatives may be produced with frozen sections. Therefore, frozen section results are only preliminary and need to be confirmed by a routine fixed sample, which takes about 2 working days to analyze (Harris et al. 1997).Excisional Biopsy as a Surgical Treatment
The primary function of an excisional biopsy is to diagnose cancer. However, it can also serve as definitive surgery by removing the cancerous tumor from the breast. Definitive surgery consists of the removal of the entire tumor plus a surrounding amount of normal tissue (a margin) and possibly the axillary lymph nodes.
The pathologist will then inspect the tumor margins. If normal tissue surrounds the entire tumor (which is termed clean or uninvolved or negative margins), the surgery is considered definitive and no additional surgery is needed. If there is insufficient normal tissue surrounding the tumor ("dirty" or involved or positive margins), additional surgery is required to remove the remaining tumor.
The excisional biopsy has many advantages over a needle biopsy. It provides a larger sample size, ensuring far fewer false negative results, and provides accurate information on factors such as tumor size, tumor grade, and the presence of estrogen receptors, all of which are key factors in deciding on a treatment plan.
The excisional biopsy has some disadvantages. It is a far more extensive procedure than a needle biopsy. If a large amount of tissue is removed, the appearance and feel of the breast may also be changed. An excisional biopsy is also expensive and has a longer, more painful recovery period.Incisional Biopsy
Incisional biopsy is a surgical procedure done most often on women with advanced-stage cancer whose tumors are too large to be removed as an initial treatment. Only a portion of the tumor is removed, providing a sufficient amount of tissue to procure information essential for developing a treatment plan.Continued
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