Wire localization

A wire localization is a procedure that uses a fine wire to mark the exact site of an abnormality. It’s done before an excisional biopsy, which is surgery to remove a lump or abnormal area so the tissue can be checked for cancer cells. Wire localization may also be called fine-wire localization or needle localization.

Wire localization is done to mark the exact location of an abnormality in the breast. It’s usually done before a type of surgery called an excisional biopsy.

Wire localization can be used to mark:

• a lump that cannot be felt (is non-palpable) during a physical exam
• an abnormal area to help the surgeon find the area during surgery
• an area of interest so the surgeon can remove only the necessary tissue during surgery instead of removing the entire breast (called a mastectomy)

Wire localization is done in the imaging department of a hospital.

First, an imaging test such as an x-ray, mammography, MRI, CT scan or ultrasound is used to help find the area to be sampled. The area is then numbed using a local anesthetic.

Next, the radiologist places a hollow needle into the area. A thin wire gets inserted through the centre of the needle. Once the wire is in place, the needle is removed. One end of the wire remains outside the breast. The wire is often taped to the skin so that it won’t move until the excisional biopsy is done.

In some treatment centres, a tiny metal “seed” may be used to mark the area instead of a wire. The seed has a small amount of radiation and is removed during the excisional biopsy.

After wire localization, you will have an excisional biopsy to remove the lump or abnormal area. This is done in an operating room. During the excisional biopsy, the surgeon removes the lump or abnormal area. The wire or seed that has guided the surgeon to the area is also removed.

The tissue that the surgeon removed is sent to a pathology lab. A pathologist (a doctor who specializes in the causes and nature of disease) looks at the cells under a microscope to see if any are cancerous. The pathology report shows what types of cell are present, their characteristics and whether they are normal, cancerous or abnormal but non-cancerous.

If the report shows that the cells are cancerous, they may need to be studied further. You may need other tests to find out the type of tumour it is, how fast the cells are growing and if cancer cells have spread to the surrounding normal tissue.