TOPLINE:

In patients with small early gastric cancer, underwater endoscopic mucosal resection (UEMR) performed without submucosal saline injection produced a higher rate of complete histologic resection than conventional EMR (CEMR) and was used more often for larger lesions and lesions with elevated tumor morphology.

METHODOLOGY:

• EMR is routinely used for small early gastric cancer because of its simplicity and speed, but complete histologic resection rates can be low. UEMR has shown promise for colorectal polyps yet had not been directly compared with CEMR for early gastric cancer.
• Researchers in Japan conducted a retrospective study comparing UEMR with CEMR for intramucosal early gastric cancer ≤ 20 mm without ulceration performed between January 2014 and March 2024.
• The groups were propensity score matched based on operator expertise, tumor location, endoscopic size, morphological type, and treatment period.
• The primary outcome was the rate of complete histologic resection.

TAKEAWAY:

• Investigators included 32 patients who underwent UEMR and 89 CEMR; after matching, 26 lesions per group were analyzed (UEMR: median age, 77 years; 69% men; CEMR: median age, 76 years; 85% men).
• UEMR achieved a significantly higher complete histologic resection rate than CEMR (96% vs 69%; P = .024).
• Before propensity score matching, UEMR cases had relatively larger endoscopic tumor size (P = .036) with more elevated tumor morphology (P < .001) than CEMR.
• Aspiration pneumonia developed in one patient in each cohort, indicating that water immersion in the stomach does not elevate the risk for aspiration pneumonia.
• No delayed bleeding occurred after UEMR; one delayed hemorrhage was reported in the CEMR group before matching.

IN PRACTICE:

“UEMR is preferable to CEMR for small [early gastric cancer] that fulfill the absolute indication of EMR, mainly located in the greater curvature, as it provides a better [complete histologic resection] rate,” the authors concluded.

SOURCE:

This study was led by Yoshiaki Ando, Osaka International Cancer Institute, Osaka, Japan. It was published online in the Journal of Gastroenterology and Hepatology.

LIMITATIONS:

This study was conducted at a high-volume cancer center with expert endoscopists determining indications, thus limiting generalizability. The underwater EMR sample size was relatively small, and certain unknown confounding factors remained unadjusted for in the propensity score analysis.

DISCLOSURES:

This study received no specific funding. Five authors reported receiving honoraria from various pharmaceutical, medical devices, and healthcare companies, including Boston Scientific, Daiichi-Sankyo, and AI Medical Service.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.