Diagnostic utility of small-caliber and conventional endoscopes for gastric cancer and analysis of endoscopic false-negative gastric cancers

Figure 1 Locations of 17 false-negative gastric cancers. A: Open circles indicate the false-negative gastric cancer (FN-GC) lesions found by small-caliber endoscope (SC-E), and closed circles indicate the FN-GCs found by conventional endoscopy (C-E); B: Open circles indicate FN-GC lesions that invaded to the mucosal layer and closed circles indicate the FN-GC lesions that invaded to the submucosal layer. Open triangles indicate lesions with unknown depth; C: Open circles indicate the FN-GC lesions of pathologically differentiated types (papillary adenocarcinoma, well or moderately differentiated adenocarcinoma) and closed circles indicate the FN-GC lesions of pathologically diffuse types (poorly differentiated adenocarcinoma or signet ring cell carcinoma). m: Mucosal layer; sm: Submucosal layer; pap: Papillary adenocarcinoma; tub1: Well differentiated tubular adenocarcinoma; tub2: Moderately differentiated adenocarcinoma; por: Poorly differentiated adenocarcinoma; sig: Signet ring cell carcinoma; AW: Anterior wall; PW: Posterior wall; LC: Lesser curvature; GC: Greater curvature; U: Upper; M: Middle; L: Lower.