By Marilynn Larkin
NEW YORK (Reuters Health) - 3/4/2019
Endoscopic clip closure after resection of large sessile polyps in the proximal colon reduced the risk of post-procedure bleeding in a multicenter randomized trial, researchers say.
Dr. Heiko Pohl of Dartmouth Geisel School of Medicine in Hanover, New Hampshire and colleagues assigned 919 patients with large non-pedunculated colon polyps (20 mm or larger) to groups that did or did not undergo endoscopic clip closure after resection.
Post-procedure bleeding was defined as a severe bleeding event that required hospitalization, a blood transfusion, colonoscopy, surgery, or another invasive intervention within 30 days.
As reported online March 15 in Gastroenterology, post-procedure bleeding occurred in 3.5% of patients in the clip group and 7.1% in the control group.
Among 615 patients (66.9%) with a proximal large polyp, the risk of bleeding was significantly lower in the clip group (3.3% vs. 9.6%).
No significant difference between the clip and control groups was seen following resection of distal polyps.
The median number of clips needed to completely close the resection defect for any polyp was four, with no difference in the number of clips used for distal or proximal polyps.
Among those with post-procedure bleeding, bleeding started at a median seven days following the procedure in the clip group and one day in the control group. There was no difference in length of stay or need for blood transfusions.
The effect of clip closure was independent of antithrombotic medications or polyp size. Serious adverse events occurred in 4.8% of patients in the clip group and 9.5% of controls.
Type of adverse event did not vary significantly between groups. However, perforations were more frequent in the control group (6 vs. 3). Only control group patients experienced delayed perforations (3 patients) and required surgery (3 patients).
More patients in the control group required colonoscopy due to a severe adverse event (4.5% vs. 1.5%).
"Personally, I was surprised by the results," Dr. Pohl told Reuters Health by email. "We have probably all seen patients who had a bleeding complication even after clips were placed. But the results of the study have changed my practice. I now attempt to close all mucosal defects after resection of non-pedunculated polyps 20 mm or larger that are located in the proximal colon, but not in the distal colon."
"The benefit was seen despite the fact that 13% of polyp sites could not be closed, and another 18% could only partially be closed," he noted. "Therefore, clip closure should always be attempted."
"There is still a question whether clip closure is cost effective," he added.
"Clips are expensive," he continued. "A median of four clips were used per resection site. Twenty-eight patients would have to undergo clip closure to prevent one post-procedure bleeding event if all sites were clipped, or 16 patients if only proximal polyps were clipped. Is it worthwhile to treat 16 patients with a proximal polyp to prevent one patient from having a significant bleeding that can be life threatening, requires hospitalization and possible blood transfusion or an emergent colonoscopy? (This) has to be shown in a cost-effectiveness analysis."
Dr. Nikhil Kumta, Director of Surgical and Bariatric Endoscopy at Icahn School of Medicine at Sinai in New York City, told Reuters Health by email, "I agree that the results are practice- changing: prophylactic clips should be used to close large polyp resection sites in the right colon to reduce the risk of delayed bleeding."
"The downside is the cost of using multiple clips," he acknowledged, and like Dr. Pohl, he noted that "future studies will need to evaluate the cost-effectiveness of this strategy."
The study was funded by Boston Scientific. Dr. Pohl has received funds from the company and eight coauthors are consultants to it.