Breast cancer treatment: Nitinol’s solution for effective biopsy markers

Breast-conserving surgery, also known as lumpectomy, is a treatment option for many women with early-stage breast cancer.  For this operation, the surgeon removes only the cancerous tissue along with a margin of healthy breast tissue surrounding it. A pathologist then examines this margin to confirm that no cancer cells remain. 

Lumpectomy surgeries are less invasive, removing less breast tissue and leaving minimum scarring. The U.S. National Institutes of Health released a statement back in 1990 stating that a lumpectomy followed by radiation was preferred over mastectomy to treat early-stage breast cancer, and current studies indicate that this is still the case.

In early-stage breast cancer, it is not uncommon for changes in the breast tissue to not be detectable via a manual examination. While a mammogram can show surgeons abnormal areas of the breast, the surgeon will need to carry out a wire-guided excision biopsy, or wire localization procedure, to precisely locate and remove the lesion. 

Alleima is a trusted partner to medical OEMs for its expertise in developing and manufacturing medical solutions such as ultra-fine wire or wire-based components. One of the company’s products is localization wire in breast cancer detection. Medical wire-based components for wire localization come in different lengths to accommodate the patient's breast size, ensuring the surgeon can reach the necessary depth within the breast tissue while leaving enough of the wire's tail exposed to facilitate the extraction.

Cacie McDorman, engineering manager at Alleima, emphasizes: “Generally the localization wires are made of either stainless steel or nitinol, which allows for flexibility and strength. Both are always important when you’re putting anything in the body.”

“They are generally twisted wires, with two different twisting patterns – one is tighter than the other. That functions as a cue for the doctors when they are inserting it into the breast tissue as to how far it needs to go.”

Following a biopsy where tissue samples have been taken, doctors may use a tool to place a clip made of surgical-grade material called marker.  This marker will be visible on a mammogram and is crucial for doctors to identify the exact biopsy site, especially if the patient is undergoing chemotherapy, which may alter the size and shape of the area. 

Some challenges with traditional biopsy markers include their inability to immediately anchor into the tissue when deployed from the applicator. While certain markers are designed to address this issue, it can take up to 24 hours for them to fully attach. This delay creates a risk of marker migration after the procedure, leading to inaccurate identification of the biopsy site in subsequent mammograms.

Additional challenges arise when a patient undergoes multiple biopsies. In such cases, doctors often use differently shaped markers to distinguish between biopsy sites. However, most markers are 2D and can appear significantly different depending on the viewing angle. For example, an “X”-shaped marker may appear as a straight line when viewed from the side.

Nitinol’s unique shape memory properties allow it to address many of the challenges associated with traditional biopsy markers. Its ability to be compressed and loaded into an applicator means that, once deployed, it instantly returns to its original shape and securely anchors into the tissue. This immediate fixation eliminates the risk of marker migration. 

Alleima also produces markers in a variety of distinct shapes, enabling doctors to use different markers for multiple biopsies. Unlike most 2D markers on the market, this pioneering 3D marker system can easily be identified from any angle. Developed in close collaboration with its customers, these systems leverage Alleima’s nitinol expertise and precision manufacturing capabilities, offering a more effective solution for cancer biopsy markers. 

Alleima’s engineering services for complex, life-changing medical solutions draw on a wide range of materials, including stainless steel, nitinol, and cobalt-chromium alloys, all known for their high quality, strength, and durability. By leveraging its extensive processing capabilities, the company’s solutions are particularly well-suited for applications that require navigating the body’s complex and delicate structures, such as catheters, guidewires, deep brain stimulation, and remote patient monitoring, among others.  

To find out more about Alleima’s engineering solutions and nitinol processing capabilities visit their website.