Fine Needle Aspirate (FNA)
A fine needle aspirate (FNA) may be done if a mass is palpable (can be felt). This is done by removing some of the cells with a small, hollow needle so that the pathologist can look at them with the microscope. This may give enough information to tell if the mass is benign or malignant. If fluid is withdrawn, this nearly always represents a benign finding and the fluid is not usually tested. FNA may also be used to test lymph nodes under the arm.
Core Needle Biopsy
A core needle biopsy samples a larger amount of tissue for the pathologist to examine and is done under a local, or numbing, anesthetic. It is often done with the help of an imaging study like ultrasound, mammogram (called stereotactic needle biopsy), or MRI. A small, metal clip is usually left to mark the area where the biopsy was taken for future reference. This marker clip will remain in the breast unless the pathology results show something that needs to be removed. This procedure takes about 30 to 60 minutes. You can resume normal activities immediately after it is done.
An excisional biopsy is performed by the surgeon if the abnormality cannot be biopsied with ultrasound, mammogram, or MRI. This is much less common than it used to be, and only a small percent of lesions are biopsied this way. After using local numbing medicine, usually with a medication that makes you sleepy, the surgeon makes an incision on the breast in order to remove the abnormal tissue. This is sometimes done in the doctor’s office or in an outpatient surgery center. If the abnormality cannot be felt, it may be necessary for a guide wire to be placed into the breast to mark the location (called a needle-localized excision). The wire is placed by the radiologist on the first floor immediately before the procedure.
Punch Skin Biopsy
A punch skin biopsy is performed in the surgeon’s office using local anesthesia to numb the skin before a small piece of skin and tissue is removed. This technique is used only for findings that are seen in the skin of the breast.