Wire localization biopsy

A wire localization biopsy is a procedure that uses a fine wire to mark the exact location of a lump or abnormality. It is done before a surgeon does an excisional biopsy to remove the lump. This procedure may also be called wire localization, fine-wire localization or needle localization.

Why wire localization biopsy is done

A wire localization biopsy is most commonly used to locate lumps or abnormalities in the breast but it may be used for other parts of the body as well. It can be used to:

  • remove a lump that cannot be felt (is non-palpable)
  • remove a small abnormal area that is hard for the surgeon to locate
  • remove a tissue sample if more than one abnormality is seen on an x-ray
  • help the surgeon remove a small amount of normal tissue around the abnormality (a margin) and lessen visible damage to the area

How wire localization biopsy is done

The first part of a wire localization biopsy is done in the x-ray department of a hospital.

  • An x-ray or ultrasound is used to help locate the area to be sampled.
  • A local anesthetic is often used to numb the area.
  • The radiologist places a special hollow needle into the area.
  • A thin wire with a small hook on the end is inserted through the centre of the needle. The needle is removed once the wire is in place.
  • The wire is often taped to the skin so it won’t move until the biopsy is done.

The second part of a wire localization biopsy is done in an operating room.

  • The x-ray and the wire help guide the surgeon to the tissue to be removed.
  • The lump is surgically removed and a sample of the tissue is sent to a lab to be looked at under a microscope. The surgeon removes the wire at the same time.
  • An x-ray of the tissue that was removed (called a specimen x-ray) is taken to confirm that the abnormal tissue has been completely removed.

A radioactive seed localization is similar to a wire localization and may be done in some treatment centres. Once the x-ray or ultrasound locates the area to be sampled, a tiny low-dose radioactive seed is placed to mark the location.

What the results mean

Biopsy samples are sent to a pathology lab. A pathologist (a doctor who specializes in the causes and nature of disease) looks at the cells to see if they contain cancer. The pathology report shows the type of cells 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 further tests to find out the type of tumour, how fast the cells are growing and if cancer cells have spread to the surrounding normal tissue.

What happens if the result is abnormal

Your doctor will decide whether further tests, procedures or treatment are needed.

Expert review and references

  • American Cancer Society. Testing Biopsy and Cytology Specimens for Cancer. Atlanta, GA: American Cancer Society; 2010.
  • Dollinger M, Ljung BM, Morita ET, Rosenbaum EH. How cancer is diagnosed. Ko AH, Dollinger M, Rosenbaum E. Everyone's Guide to Cancer Therapy: How Cancer is Diagnosed, Treated and Managed Day to Day. 5th ed. Kansas City: Andrews McMeel Publishing; 2008: 2:17-30.
  • Fischbach F. & Dunning MB. Manual of Laboratory and Diagnostic Test. 9th ed. Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins; 2009.
  • National Cancer Institute. Cancer.gov Dictionary. Bethesda, MD: National Cancer Institute;
  • Vogel WH. Diagnostic evaluation, classification and staging. Yarbro CH, Wujcki D, Holmes Gobel B (eds.). Cancer Nursing: Principles and Practice. 7th ed. Sudbury, MA: Jones and Bartlett; 2011: 8:166-197.

Medical disclaimer

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