Biopsy

To confirm a diagnosis of DCIS, a biopsy needs to be done. The biopsy removes a tissue sample which is studied under a microscope to see if cancer cells are present.

For the purpose of this course, we are going to divide biopsies into 3 types. They are the needle biopsy, image-guided biopsy, and the surgical biopsy. Depending on the resource used, the biopsies may be categorized, or described, in different ways. The choice of which biopsy to use depends on whether there is a lump that can be felt, or as in DCIS, only a change seen on an imaging test.

Needle biopsies: When a lump can be felt, or the microcalcification changes seen on mammogram are accessible, a needle biopsy can be done. Fine needle aspiration withdraws cells or fluid from the lump, and a core needle biopsy removes a sample of tissue. The biopsy may be done by a radiologist, surgeon or a pathologist. With DCIS, the provider commonly uses the mammogram to guide the biopsy. Before insertion of the core needle, the area is numbed with local anesthetic; with fine needle aspiration, local anesthetic may or may not be used.

Image-Guided Biopsy: This is the biopsy most often done with DCIS, as the breast change cannot be felt. X-rays (stereotactic mammography) or sound waves (ultrasound) pinpoint the breast change. The area is numbed, and a tissue sample is removed either with a core needle, or a vacuum-assisted probe.

Surgical Biopsy: This biopsy is usually done in the operating room under general anesthesia, where part or all of the "breast change" can be removed. The surgeon numbs the area. If the breast change cannot be felt, image-guidance (mammogram and/or ultrasound) locates the part of the breast that has microcalcification changes. One or more wires may be inserted into the breast near the lump or breast change; this is wire localization. An incision is made and the area in question is removed along with a margin of normal tissue. After excision the specimen may be x-rayed to insure that the specimen matches the suspected area and to help orient the pathologist.

When local anesthetic is used, as in the first 2 biopsy categories, the area is numb before the sampling needle or probe is inserted. The local anesthetic greatly decreases or totally eliminates pain. While there is no pain, the procedures require the woman to remain still for 30 to 40 minutes. That can be difficult to do depending upon size and other health conditions. If a woman's breast is small, or the calcifications are either very deep within the breast, or very superficial, needle and image-guided biopsies may not be the best choice.