Clinical usefulness of dilated vessels in early gastric cancer found by magnifying endoscopy with narrow-band imaging for predicting minute submucosal invasion

Background: Dilated vessels (D-vessels) in magnifying endoscopy with narrow-band imaging (M-NBI) have recently been found to be informative for distinguishing minimally submucosal invasion (SM1) from mucosal invasion (M) of early gastric cancer. On the other hand, non-extension signs in white light imaging are known to be well correlated with deeper submucosal invasion (SM2), but not with SM1. Herein, we compared D-vessels with non-extension signs in terms of diagnosability of the tumor depth. Methods: We included 336 patients of type 0-II early gastric cancer in our hospital to whom endoscopic submucosal dissection was performed from January 2016 to February 2021. D-vessels and non-extension signs were retrospectively searched by 2 endoscopists. Results: The number of patients was M/SM1/SM2 = 294/21/21. D-vessel’s sensitivity, specificity, positive predictive value, negative predictive value and accuracy in predicting submucosal invasion were 76.2%, 95.6%, 71.1%, 96.6% and 93.1%, respectively. D-vessels were significantly more sensitive than non-extension signs to predict submucosal invasion (76.2% vs 50.0%, p=0.023) and particularly SM1 (71.4% vs 23.8%, p=0.0048). Conclusion: D-vessels in M-NBI may have the potential to foretell submucosal invasion, especially SM1, compared with existing endoscopic findings.