(Breast Scintigraphy, Scintimammography, Radionuclide Breast Imaging, Molecular Breast Imaging)

Procedure Overview

What is a breast scan?

A breast scan is a specialized radiology procedure used to assess the breasts when other examinations have been inconclusive.

A breast scan is a type of nuclear radiology procedure. This means that a tiny amount of a radioactive substance is used during the procedure to assist in the examination of the breasts. The radioactive substance, called a radionuclide (radiopharmaceutical or radioactive tracer), is absorbed by certain types of body tissues.

The radionuclide used in breast scans is usually a form of technetium. Once absorbed into the breast tissue, the radionuclide emits a type of radiation, called gamma radiation. The gamma radiation is detected by a scanner, which processes the information into a picture of the breasts.

By measuring the behavior of the radionuclide in the body during a nuclear scan, the physician can assess and diagnose various conditions, such as tumors, abscesses, hematomas, organ enlargement, or cysts. A nuclear scan may also be used to assess organ function and blood circulation. Cancer cells take up more of the radionuclide than normal cells, and the cancer cells can be detected with a specialized camera.

A breast scan is used to identify breast cancer, especially in younger women, who usually have denser breasts than those of older women and for whom mammography may not be accurate. Other reasons for dense breast tissue can include fibrocystic disease, fatty tissue, previous breast surgery, radiation therapy, chemotherapy, biopsy, or breast implants.

Other related procedures that may be used to evaluate breast problems include mammography, breast ultrasound, and breast biopsy. Please see these procedures for more information.

Anatomy of the Breasts

Each breast has 15 to 20 sections, called lobes, which are arranged like the petals of a daisy. Each lobe has many smaller lobules, which end in dozens of tiny bulbs that can produce milk.

The lobes, lobules, and bulbs are all linked by thin tubes called ducts. These ducts lead to the nipple in the center of a dark area of skin called the areola. Fat fills the spaces between lobules and ducts.

There are no muscles in the breast, but muscles lie under each breast and cover the ribs.

Each breast also contains blood vessels and vessels that carry lymph. The lymph vessels lead to small bean-shaped organs called lymph nodes, clusters of which are found under the arm, above the collarbone, and in the chest, as well as in many other parts of the body.

Reasons for the Procedure

A mammography is generally used for routine screening, but a breast scan may be used when the results of mammography are uncertain or as an adjunct to mammography.

Other indications for a breast scan include follow-up after surgery, chemotherapy, or other breast cancer treatment. Staging of breast cancer may be determined with a breast scan. Another type of nuclear scan, called lymphoscintigraphy, may be used to determine whether the cancer has spread to the lymph nodes of the armpit.

There may be other reasons for your physician to recommend a breast scan.

Risks of the Procedure

The amount of the radionuclide injected into your vein for the procedure is small enough that there is no need for precautions against radioactive exposure. The injection of the radionuclide may cause some slight discomfort. Allergic reactions to the radionuclide are rare, but may occur.

For some patients, having to lie still on the scanning table for the length of the procedure may cause some discomfort or pain.

Patients who are allergic to or sensitive to medications, contrast dyes,  or latex should notify their physician.

If you are pregnant or suspect that you may be pregnant, you should notify your physician due to the risk of injury to the fetus from a breast scan. If you are lactating, or breastfeeding, you should notify your physician due to the risk of contaminating breast milk with the radionuclide.