MOLLI wire-free breast localization

A more comfortable approach to breast localization

When breast imaging finds an area of concern that needs to be removed, it may not always be something you or your surgeon can feel. Breast localization helps your surgeon pinpoint that area during surgery so the right tissue can be accurately removed.

MOLLI is a wire-free breast localization technology that uses a tiny magnetic marker to identify the area your surgeon needs to find. Unlike traditional wire localization, which uses a thin wire that extends outside the breast, the MOLLI marker stays completely inside your breast until surgery. This wire-free approach can help make the experience more comfortable and convenient for you.

What is MOLLI?

MOLLI is a technology used to help surgeons locate breast abnormalities that may be difficult or impossible to feel, including areas identified through a mammogram, ultrasound or other breast imaging.

Instead of using a wire that extends outside the breast to mark the area, a radiologist places a small magnetic marker directly into the targeted breast tissue. The marker is smaller than a grain of rice and can be placed days or weeks before your surgery.

During your procedure, your surgeon uses a handheld detection device to locate the marker and guide them to the targeted tissue.

Why might you need it?

You may need breast localization if imaging identifies an abnormal area that needs to be surgically removed but cannot easily be felt during a breast exam.

Breast localization gives your surgeon a precise location to follow during your procedure. It may be used for areas such as:

  • Breast masses or abnormalities found through imaging
  • Areas of concern identified during breast cancer screening
  • Nonpalpable breast lesions, which are areas that can be seen on imaging but cannot be felt
  • Breast cancers that require surgical removal

Your breast care team will determine whether MOLLI is appropriate for your procedure and explain what to expect.

How does MOLLI work?

MOLLI separates breast localization from the day of surgery, giving you and your care team more flexibility in planning your procedure.


Before surgery

A radiologist uses breast imaging, such as ultrasound, to identify the area that needs to be removed. Using a needle, the radiologist places a tiny magnetic MOLLI marker directly into the targeted breast tissue. The needle is then removed, leaving only the marker in place until your surgery.

The marker can be placed days or weeks ahead of time, so localization does not have to happen immediately before your procedure.

During surgery

Your surgeon uses a pen-like detection device to locate the magnetic marker. The system provides audio and visual guidance that helps your surgeon find the targeted area and remove the appropriate tissue.

After the tissue is removed, the technology can also help your surgical team assess the location of the marker within the removed tissue.

Benefits of wire-free breast localization

For patients who are candidates for MOLLI, wire-free localization can offer several benefits compared with traditional wire localization, including:

  • No external wire: The magnetic marker remains entirely within the breast until it is removed during surgery.
  • More flexibility: The marker can be placed ahead of your surgery rather than requiring localization on the same day.
  • Precise surgical guidance: Your surgeon can use the MOLLI detection system to locate the targeted breast tissue during your procedure.
  • A more comfortable experience: Eliminating an external wire may help make the time leading up to surgery more comfortable and less stressful.

Advanced breast care close to home

Facing an abnormal breast imaging result or breast cancer diagnosis can bring uncertainty. Having access to technology designed to make the next steps more precise and comfortable can make a difference in your experience.

At CHRISTUS Health, breast care brings together imaging, surgical expertise and advanced technology to help guide you from diagnosis through treatment. MOLLI wire-free breast localization gives eligible patients another option for precise breast surgery without the need for traditional wire localization.