“EFTR is an emerging technique for removal of nonlifting colorectal lesions but data on resection of malignant tumors are limited,” wrote Armin Kuellmer, MD, of the University of Freiburg (Germany), along with his colleagues.
The researchers retrospectively studied a cohort of 156 patients with histologically confirmed adenocarcinoma from 2015 to 2018 included in a German endoscopy registry. The most common indication for the procedure was removal of nonlifting lesions (n = 92), followed by resection of malignant polyps (n = 64). Dr. Kuellmer and his colleagues examined the efficacy, safety, and clinical significance of this novel technique.
The primary outcomes measured were technical success and R0 resection, which were defined as the macroscopic complete removal of the lesion and complete histologic removal with no evidence of malignant tissue in a tissue sample, respectively.
“Low-risk versus high-risk lesions are difficult to discriminate before resection as criteria are based on histological features,” the researchers wrote. “The study underlines the potential of EFTR to exactly discriminate between high-risk versus low-risk tumors to aid decision[s] for the optimal individual treatment strategy.”
After analysis, the investigators reported a technical success rate of 92.3% in patients who underwent the procedure and that the R0 resection rate was 71.8% in the same group.
“Reported technical success rates of EFTR for other indications [mainly nonlifting adenomas] range from 75% to 100% and are in line with our data,” they explained.
In a subgroup analysis, Dr. Kuellmer and his colleagues saw a higher R0 resection rate in patients who underwent the procedure for removal of malignant polyps (group 1) versus nonlifting lesions (group 2) (87.5% vs. 60.9%; P less than .001).
“This [difference] may be due to the fact that group 1 mainly consisted of low-risk tumors and small resection scars whereas the majority of lesions in group 2 proved to be more advanced tumors,” they added.
With respect to safety, 21 treatment-related adverse events were seen in the cohort, which were classified as either mild, moderate, or severe. Of these events, six were severe, defined as possibly life-threatening or requiring surgical intervention to resolve.
“The rate of major [adverse events] including perforation is in line with reported data on EFTR for other indications [0%-5%],” they wrote.
The authors acknowledged that a key limitation of the study was the retrospective cohort design. As a result, specific treatment strategies and procedural expertise could have varied across the participating centers. “We therefore cannot provide data on how much patients in total have been evaluated for EFTR,” they wrote.
Moving forward, the researchers highlighted the importance of conducting prospective studies to assess whether EFTR is a viable, safe, and effective treatment option for patients with early colorectal cancer.
“For patients with high-risk lesions unfit for surgery, [EFTR] might as well be a valuable option for local endoscopic treatment,” they concluded.
Funding sources and conflicts of interests were not reported.
SOURCE: Kuellmer A et al. Gastrointest Endosc. 2019 Jan 14. doi: 10.1016/j.gie.2018.12.025.