December 11, 2018
An estimated 23 percent of patients who have breast conserving surgery (BCS) need additional surgery because post-operative pathology identifies positive margins. Each additional surgery costs more than $16,000 and poses a significant burden to patients. To help combat this issue, Johns Hopkins breast surgeons are leading a large multicenter trial to test a promising device that assesses margins at the time of surgery.
“Reoperation after lumpectomy is a big problem,” says David Euhus, director of breast surgery. “The gold standard to assess margins is pathology, but we hope an intraoperative device can make that final assessment negative most of the time and reduce the number of reoperations.”
A Comparison of Results
Since 2013, the team of breast surgeons, led by Lisa Jacobs, has developed and tested a handheld device to assess the margins of excised tissue at the time of surgery. What makes the device unique is that it uses optical coherence tomography (OCT) with interferometric synthetic aperture microscopy (ISAM).
OCT is commonly used in ophthalmology and generates images that look similar to ultrasound but have higher resolution and more shallow imaging depth. In real time, it uses near-infrared light to provide high-resolution, cross-sectional optical images of microscopic tissue.
To test the feasibility of the device and to determine its potential impact on patient outcomes, Jacobs and her colleagues conducted a pilot study with specimens from 46 patients with early stage breast cancer. The results of analyses of images from the device were compared with post-operative pathology results. The pathology showed eight patients had at least one positive margin. The device identified positive margins in five of these, meaning reoperation could potentially have been avoided for those five.
In the same study, which was published in 2015 in Annals of Surgical Oncology, pathology showed 35 patients had all negative margins. Of those, 63 percent had at least one false-positive margin identified by the device. In these cases, each patient would potentially have had additional shave excisions during surgery to remove approximately 1 percent of overall average breast volume.
“The challenge with any margin technology is similar,” says Euhus. “If the technology is too sensitive, it will call everything cancer and surgeons will excise too much tissue. If the sensitivity is too low, patients will leave the OR with positive margins.”
An Atlas to Help Analyze Images
To help distinguish between features in OCT images, Jacobs and colleagues recently performed a histology-correlated study of specimens from 26 patients. Images from the OCT device and the corresponding histology were used to create guidelines to help surgeons analyze the OCT images. The study was accepted in late 2018 for publication in Surgical Innovation.
“This work could change the patient experience by reducing the burden of care on the patient,” says Christopher Wolfgang, division chief of surgical oncology. “This is very important for patients and hospitals alike.”
To discuss a patient case or to make a referral for breast surgery, call 443-997-1508.
