Ultrasound is an excellent examination when mammography is suspicious, but it cannot be a substitute for the screening mammogram. As noted in the section on Screening, ultrasound is the primary examination in young, pregnant, or lactating women with palpable abnormalities. It is also routinely performed on women with clinical findings whose mammograms are unrevealing and on those whose mammograms show an area that requires further evaluation. Ultrasound is also used to guide interventional procedures, such as needle localization, fine needle aspiration, and core biopsy.
A reliable aid in the diagnoses of most breast cysts, ultrasound can be used to guide benign cyst puncture for those who are symptomatic or do not meet stringent criteria for diagnosis of a benign cyst on ultrasound. In addition, it can provide reassurance that no mass underlies a questionable palpable area. According to recent evidence, ultrasound can aid in the benign-malignant differentiation of solid breast masses and prevent biopsy for many noncancerous masses, such as fibroadenomas.
Other Diagnostic Procedures Performed in Radiology
An ultrasound guided biopsy is necessary when the breast abnormality is not able to be felt. The ultrasound machine (sonogram) allows the physician to visualize the abnormality so a biopsy can be taken. Either a Fine Needle Aspiration (FNA) or a core biopsy can be obtained using ultrasound. Immediate results are available with ultrasound FNA, but the core samples require 48 to 72 hours to be read by the pathologist. The biopsy is done as an outpatient. The patient goes home with a small dressing or bandage.
A stereotactic biopsy is used for non-palpable lesions best seen on mammography. Often times microcalcifications, or tiny abnormal deposits of calcium salts, appear as little white specks on the mammogram. These tiny abnormalities require a stereotactic biopsy. Microcalcifications can be classified as benign, indeterminate or highly suspicious. Indeterminate or suspicious microcalcifications, also called pleomorphic require biopsy.
The patient lies on her belly on a special table which allows her breast to hang freely through a hole in the table.
An imaging/biopsy machine is under the table and computer guidance directs the physician to the exact place the biopsy needs to be taken. The procedure lasts 40 minutes to one hour and, as with a freehand or ultrasound guided biopsy, the patient goes home with only a small bandage. Pathology results are completed in 48 to 72 hours because tissue samples are taken as is described under Core Biopsy.
Fine needle aspiration (FNA) is the insertion of a small-gauge needle with an attached empty syringe into the lump. The procedure can be done in the office with a physician and nurse. The physician numbs the breast with a needle injection. Once the area is numb, the doctor inserts a needle and aspirates to collect fluid and cells for analysis. Aspiration is used to collect fluid and cells from the breast lump. If the lump is a cyst, which is totally benign (noncancerous), the physician will be able to aspirate fluid and the lesion may disappear. Fibroadenoma, also a benign condition, may be identified by pathology.
A core biopsy is simply performed with a larger needle than the FNA. It provides a core of tissue for the pathologist to evaluate. The procedure can be done in the office by physician and nurse. The physician will numb the breast with a needle injection. Once the area is numb, the doctor will make a very tiny incision and insert the core biopsy gun into the suspicious palpable abnormality and take three samples of tissue. The gun makes a loud pop when taking the tissue sample, but should cause no discomfort.
The procedure takes about 15 minutes and the tissue samples are sent to the pathologist for evaluation. Immediate results are not available on core biopsies, but are usually available in 48 to 72 hours. Your physician will call with a diagnosis.
Magnetic Resonance Imaging (MRI) has been used more and more frequently to evaluate breast tissue. MRI is valuable in the following conditions:
- When a patient has breast implants and the mammogram films are not able to capture all of the breast tissue. It is also used to evaluate rupture or leakage of implants.
- When it is believed that there is multifocal or multicentric disease (more than one tumor, or ductal carcinoma in-situ in more than one quadrant of the breast).
- Anytime lobular carcinoma is identified.
We have found that MRI can provide clarity about the extent of disease in these situations when conventional breast imaging (mammography and ultrasound) are not able to clearly visualize the abnormalities. MRI is not recommended as part of a routine screening.
Occasionally a lump or abnormality found on mammogram or U.S. requires removal of the area of concern.
If the area of concern is able to be felt by the physician, the patient will be asked to schedule surgery in the operating room. After a brief history and physical exam, as well as lab work, the patient will be taken into the operating room. An IV will be inserted and the patient will receive medication that will allow them to fall asleep.
A small incision is made in the breast and the area of concern is removed with a rim of normal breast tissue all around it. The procedure lasts about 30 minutes and the patient will go home with absorbable sutures and a few steri-strips. Pathology on the excised abnormality will be available in 48 to 72 hours.
The patient may be a little sleepy the rest of the day, but should be able to return to normal activities the next day.
If the abnormality cannot be felt by the physician, needle localization may be required. When needle localization is required, the patient is asked to report to radiology one hour prior to the scheduled surgery. In radiology, a thin wire is placed in the breast (either with ultrasound or stereotactic guidance) to mark the abnormal area for the surgeon. This is done to assure the abnormality is removed. The wire is removed in the operating room along with the suspicious area.
Historically, during breast cancer surgery, 10 to 20 lymph glands in the armpit were removed and analyzed to determine whether or not the initial cancer had spread. Even though studies showed that less than half of all women with breast cancer had lymph node involvement, most women went through this surgery which caused negative side effects including swelling of the arm, discomfort or pain around the shoulder or arm, or numbness around the upper arm.
Technology has been developed that allows surgeons to only sample the most likely lymph gland where the cancer is going to spread - the sentinel lymph nodes. This procedure involves injecting a radioactive material near the tumor during surgery. A special Geiger counter like machine then traces the radioactive material to the lymph node of the armpit. Only those lymph nodes showing signs of possible cancer are removed, usually one or two nodes, and sent to a pathologist for detailed examination. If no cancer is detected, no further surgery is necessary. The advantage for the woman is minimal surgery, quicker recovery time and virtually none of the side effects of the more traditional lymph node biopsy. This procedure, called sentinel node mapping, has been used by Breast Center surgeons for more than ten years following several years of successful clinical trials.
Unfortunately, when cancer is detected it is necessary to complete the previously described historical procedure of removing many of the lymph nodes. Patients are monitored closely to promptly diagnose lymphedema (swollen arm) and other side effects of the procedure allowing quick intervention to take place. Recently published data from the National Institutes of Health (NIH) indicates women who are diagnosed and treated promptly for lymphedema return to normal arm size and function within a few months.