Margin marking before endoscopic mucosal resection (EMR) of large colorectal polyps cut the risk of recurrence by 80% when compared with traditional EMR, new data suggest.
A team of researchers, led by Dennis Yang, MD, with the Center for Interventional Endoscopy at AdventHealth, Orlando, compared polyp recurrence after patients received EMR with margin marking versus recurrence after conventional EMR in a historical control group. They conclude that the simple margin-marking strategy may offer an alternative to margin ablation.
The findings of the study were published online Nov. 29 in Gastrointestinal Endoscopy.
A single-center, historical control study
A total of 210 patients (average age, 66 years; 56.2% women) with 210 polyps (average size, 30 mm; interquartile range: 25-40 mm) had either EMR with margin marking (EMR-MM; n = 74) or conventional EMR (n = 136). The groups had similar patient and lesion characteristics.
For EMR-MM, cautery marks were drawn along the lateral margins of the polyp with the snare tip. EMR followed with resection of the healthy mucosa with the marks.
Physicians can confirm complete resection, including a healthy margin, when no cautery marks are visible after EMR, the authors write.
A follow-up colonoscopy was performed 3 to 6 months later, the results of which were compared against historical controls.
After 6 months, EMR-MM led to a lower recurrence rate compared with the historical control group with traditional EMR (8% vs. 29%, respectively; P < .001).
“This strategy allowed a more reliable wide-field EMR, which may account for why our preliminary results demonstrated an 80% reduction in the likelihood of recurrence even after controlling for other factors, including polyp size and histopathology,” the authors write.
Recurrence risk has been one of the main limitations of EMR compared with surgery, with rates from 10%-35%, the authors note, though it has fewer adverse reactions and offers better quality of life than surgery.
Dr. Yang told this news organization that multiple studies have looked at possible factors for recurrence, which is thought to primarily occur at the lateral resection margins of the polyp.
“That’s based on recent data that has shown that burning the resection margins after you actually take the lesion out reduces recurrence,” he said. “What that indirectly implies is that whenever we resect something, we may think we’ve got the entire lesion at the lateral margins, but we don’t.”
As Dr. Yang described, it was this implication that led to the premise of the study.
“If we were to somehow put visible marks outside the margins of the lesion, the marks would serve as visible cues to tell us how much more tissue we needed to resect and thereby help us get a more reliable way of ensuring clean resection margins.”
Dr. Yang and colleagues also found that EMR-MM was not linked with an increase in adverse events. On multivariable analysis, EMR-MM was the main predictor of recurrence (odds ratio, 0.20; 95% CI, 0.13-0.64; P = .003) aside from polyp size (OR, 2.81; 95% CI, 1.35-6.01; P = .008).