Gastric superficial neoplasia: high miss rate but slow progression

Background and aims Gastric superficial neoplasia (GSN) is often overlooked at endoscopy because of difficulty in identifying it. The miss rate of GSN at endoscopy and the impact on clinical outcome of the missed GSN have not been fully elucidated. In this study, we investigated these issues. Methods Among 1462 endoscopically and pathologically diagnosed gastric cancers in our hospital from January 2011 to December 2014, previous records of esophagogastroduodenoscopy (EGD) were available for 198 lesions (index lesions) and were reviewed retrospectively. Among those, 157 lesions, which were diagnosed as GSN on the basis of their EGD findings at initial endoscopy, were analyzed. Progression was defined as advanced cancer in the index lesion. Results Among the 157 GSNs, 118 (75.2 %) had not been recorded in the previous EGD report but were evident upon review of endoscopic photographs for this study. Progression to advanced cancer was observed in only 13 (8.3 %) of the 157 GSNs during a mean interval of 41 months and as long as 96 months, and the rate of progression was similar in missed and not-missed lesions (8.5 % and 7.7 %, respectively). Cumulative incidence rates of progression of missed GSNs to advanced cancer were 0.8 %, 1.7 %, 4.2 %, and 7.6 % at 36, 48, 60, and 72 months after the initial EGD, respectively. Conclusions Our findings illustrate that GSNs are often missed at endoscopy but progress slowly in most cases. Even though the rate of progression to cancer is relatively low, rigorous attempts should be made to reduce the miss rate of GSNs at EGD.