What is a breast biopsy?

Let's say you find a lump in your breast, what next? Well, the safest thing is to assume it is a tumor until proven otherwise. The only sure way to determine whether a lump is cancer is to do a biopsy. This involves taking a tissue sample for further examination in the lab, sometimes through a small needle. Sometimes surgery is done to take part of or the entire lump for testing. The results will show whether the lump is cancer, and if so, what type. There are several forms of breast cancer, and treatments are carefully matched to the type of cancer. A breast biopsy checks to see if a breast lump is cancerous (malignant) or noncancerous (benign).

There are several ways to do a breast biopsy. The sample of breast tissue will be looked at under a microscope to check for cancer cells.

• A fine-needle aspiration biopsy puts a thin needle through the skin, into the lump, and removes cells to look at. Needle aspiration may be done to see if the lump is solid or fluid-filled (cyst). If the lump is a cyst, it will go away after the fluid is removed. If there is no fluid, another type of biopsy will be done.
• A core needle biopsy uses a large needle fitted with a special tip. The needle goes through the skin to the lump or area to take out a sample of tissue about the size of a pencil lead.
• A stereotactic biopsy uses a special type of Xray during a core needle biopsy to find the area of the breast where the biopsy samples will be taken. This technique can check a lump that cannot be felt on breast examination but is seen on mammogram or MRI. A small incision is then made in the skin of the breast, and the core needle is guided by the X-ray to the biopsy site to take tissue samples. Stereotactic biopsy may not be appropriate for all types of breast lumps.
• A vacuum-assisted core biopsy is done with a hollow probe that uses a gentle vacuum to remove a sample of breast tissue. This method may be used for a core needle biopsy or a stereotactic biopsy. Vacuum-assisted biopsy can remove more tissue than a standard core needle biopsy. The single small incision does not require stitches and there is very little scarring.
• An open biopsy makes a cut in the skin and removes a sample of the lump or the entire lump. If your doctor cannot feel a lump, a small wire can be put in the suspicious area during a mammogram or MRI done just before surgery. The wire then guides your doctor to the suspicious area to take a biopsy sample.

More tests or biopsies may be needed if problems are found during the first biopsy or if your doctor is concerned about a certain area of your breast.