The impact of pre-resection endoscopic examination time on the rate of synchronous gastric neoplasms missed during endoscopic treatment

Background and study aims: Synchronous multiple gastric cancers have been reported in up to 14% of patients, but few efforts have been made to optimize techniques for detection of multiple neoplasms. We sought to evaluate whether the length of endoscopic examination before endoscopic resection affected the detection rates of synchronous gastric neoplasms. Patients and methods: Among patients referred for endoscopic treatment of gastric neoplasms (n = 1,017), we enrolled those in whom at least one other synchronous neoplasm was found during pre-resection endoscopy or during the 1-year follow-up examination. Pre-resection endoscopic examination time was compared between those in whom multiple neoplasms were completely diagnosed before resection (complete examination group) and those in whom multiple neoplasms were not fully diagnosed prior to resection but were found during follow-up evaluation (incomplete examination group). Results: Eighty-three patients were included in the study. We found no significant difference in any of the multiplicity, location, gross appearance, size, or resection type of primary lesion between the complete (n = 46) and incomplete examination (n = 37) groups. The complete examination group had a significantly longer examination time compared to the incomplete examination group (6.5 ± 2.4 min vs. 3.8 ± 1.8 min, respectively; P < 0.001). The synchronous lesions most commonly presented as the flat type (42/94 lesions, 45%) and were smaller than the primary lesions (10.0 ± 7.4 mm vs. 14.3 ± 9.1 mm, respectively; P = 0.002). Conclusions: Endoscopists should consider the possibility of synchronous gastric neoplasms and examine the whole stomach, thus allowing adequate time to reduce the risk of missed lesions.