In findings from Germany’s randomized controlled CHRONICLE trial, published in Gastroenterology , the cold technique almost eliminated major adverse events (AEs) — but at the cost of higher rates of recurrence and residual adenoma at first follow-up.
“The exact definition of the ideal lesions requires further research,” wrote investigators led by Ingo Steinbrück, MD, of the Department of Medicine and Gastroenterology at the Academic Teaching Hospital of the University of Freiburg, Freiburg im Breisgau, Germany. “Further studies have to confirm to what extent polyp size and histology can determine an individualized approach.”
Evangelisches Diakoniekrankenhaus Freiburg
Dr. Ingo Steinbrück
The researchers noted that while hot snare resection is the gold standard for larger nonpedunculated polyps of ≥ 2 cm, previous research has found the cold technique, which resects without cutting and cauterizing current, to be superior for small polyps .
“Our study suggests that sessile serrated lesions larger than 2 cm should be resected with the cold snare. Selected cases of lateral spreading tumors may also be good candidates for cold snare resection when safety concerns are paramount,” Dr. Steinbrück said in an interview. “Cold snare resection is standard of care in our center in these cases, but our data show no superiority over hot snare in terms of resection speed.”
Despite recommendations for its use, the cold snare method appears to be underused in the United States.
The Study
From June 2021 to July 2023, the 19-center intention-to-treat analysis enrolled 363 patients (48.2% women) with a total of 396 polyps and randomly assigned those with polyps of ≥ 20 mm to cold (n = 193) or hot EMR (n = 203). The primary outcome was major AEs such as perforation or post-endoscopic bleeding.
Major AEs occurred in 1.0% of the cold group and in 7.9% of the hot group (P = .001, odds ratio [OR], 0.12; 95% CI, 0.03-0.54).
Rates for perforation and post-endoscopic bleeding were significantly lower in the cold group, with 0 vs 8 (0% vs 3.9%, P = .007) perforations in the two groups, respectively, as well as 1.0% vs 4.4% (P = .040) for postprocedural bleeding.
Somewhat surprisingly, intraprocedural bleeding was also less common in the cold EMR group at 14% vs 23%.
Residual adenoma, however, was found more frequently in the cold group at 23.7% vs 13.8% (OR, 1.94; 95% CI,1.12-3.38; P = .020).
Commenting on the study but not involved in it, Seth Crockett, MD, MPH, AGAF, a professor of medicine in the Division of Gastroenterology and Hepatology at Oregon Health & Science University in Portland, Oregon, called the CHRONICLE findings very important.
Oregon Health & Science University
Dr. Seth Crockett
“Interestingly, near identical results were found in a recent report from a multicenter US trial presented at DDW earlier this year by Pohl et al., which adds credence to their findings,” he said. “While this study helps move the needle toward using cold EMR for large polyps, it also highlights an Achilles heel of this approach, a higher risk of residual polyps during follow-up.”
In other study findings, postpolypectomy syndrome occurred with similar frequency in both groups (3.1% vs 4.4%, P = .490).
As to the size factor, multivariable analysis revealed that a lesion diameter of at least 4 cm was an independent predictor of major AEs (OR, 3.37), residual adenoma (OR, 2.47), and high-grade dysplasia/cancer for residual adenoma (OR, 2.92).
In the case of suspected sessile serrated lesions, the rate of residual neoplasia was 8.3% (n = 4 of 48; 95% CI, 3.3-19.5) in the cold group and 4.8% (n = 2 of 42; 95% CI, 1.3-15.8) in the hot group (P = .681).
As for laterally spreading tumors (LSTs), Dr. Steinbrück said, “The higher recurrence rate after cold snare resection of LST nodular mixed types is unacceptable, and therefore, hot snare EMR with margin coagulation should be the treatment of choice.
“For LST granular type homogeneous and LST nongranular type without suspicion of malignancy, cold snare EMR with additional measures such as margin coagulation may be an option in selected cases — for example, when the risk of delayed bleeding is high,” he said.