Dr. Toni Storm-Dickerson stands next to her patient lying on the table in Operating Room 12. She looks at the woman’s bare chest and points to a small mark. That, she said, is where a radiologist inserted a magnet.
Storm-Dickerson grabs a probe and pushes it against the woman’s right breast. The machine beeps as Storm-Dickerson moves the probe.
Like a metal detector, the pings get louder as the wand hones in on the magnet. Then it signals when the probe is directly above the magnetic seed placed inside the woman’s breast.
The magnet marks a lesion Storm-Dickerson is set to remove — the cancerous cells that resulted in a breast cancer diagnosis. With the magnet and the probe, the breast surgical oncologist is confident in the location of the lesion.
She couldn’t say the same using previous techniques for locating lesions. But as Storm-Dickerson and PeaceHealth Southwest Medical Center test three different devices for locating lesions in breast cancer patients, the uncertainty is now a thing of the past.
“So far, we’ve done several with magnets,” Storm-Dickerson said. “And we love them.”
New technologies
For decades, breast cancer was treated with mastectomies. But as technology improved, so too did the idea of breast conservation. Chemotherapy trials provided an alternative to radical surgeries, and advances in imaging allowed for earlier cancer detection.
“With all this new imaging, we can identify cancers before they’re palpable,” Storm-Dickerson said.
But because these lesions are too tiny to be felt, surgeons needed a way to mark the cancer. Ultrasound devices can’t be used after an incision is made and mammograms only provide two-dimensional images, Storm-Dickerson said.
Traditional options for marking non-palpable tumors include wires and radioactive seeds.
Radioactive seeds are effective, but they come with a slew of costly regulations, Storm-Dickerson said, so wires are most often used.
With wires, the radiologist places a wire — 15 centimeters or longer — with a little hook at the end into the lesion in the breast tissue. The other end of the wire remains outside of the body, and is taped down to try to prevent the wire from shifting. But the tape can’t guarantee the wires won’t move.
“Breast tissue is extremely mobile,” said Storm-Dickerson, who works at Compass Oncology. “That’s the problem.”
PeaceHealth Southwest Medical Center, where Storm-Dickerson performs breast surgeries, has made the decision to switch to lesion localization devices rather than the wires. Now, Storm-Dickerson and radiologists are performing trials of three different devices to find the best fit for the medical providers and patients.
First up was the Magseed — a 1-by-5-millimeter magnetic seed, similar in size to a grain of rice. The trial was so promising, the hospital decided not to go back to using wires and, instead, is using the Magseed in between trials of the other two devices.
“We just don’t want to go back,” Storm-Dickerson said. “It’s just so much superior.”
The other devices to be tested are Savi Scout and LOCalizer. Both are larger and require larger needles to place than the Magseed. Each device will be used on about a dozen patients before a final decision is made.
Whereas wires must be placed the day of surgery, the magnet can be placed up to 30 days prior to surgery using an 18-gauge needle and local anesthetic.
During surgery, Storm-Dickerson uses the probe to locate the magnet and, with that information, decides where to make the incision and the surgical path for removing the tissue.
Before, Storm-Dickerson would view the two-dimensional mammogram images to create a model of the breast in her mind and then use wires as a guide to locate and remove the lesion.
“Now, I’m going, ‘I think it’s here,’ ” she said of locating lesions. “(With the magnet) I can say, ‘I know it’s here.’ ”
The concern with wires, Storm-Dickerson said, is removing too much unnecessary tissue if the wires moved. The wires can also be uncomfortable and intimidating for patients, she said.
With the Magseed, the procedure is quick and, since it can be done in advance, is easier to schedule at the convenience of the patient and radiologist, Storm-Dickerson said. Then, on surgery day, the patient doesn’t have to worry about other procedures and periods of sitting and waiting before the lumpectomy, she said.
“It’s much quicker, much easier and much more efficient,” Storm-Dickerson said. “For me, it’s really exciting to be able to take advantage of these things.”
