Potential Factors Predicting Histopathologically Upgrade Discrepancies between Endoscopic Forceps Biopsy of the Colorectal Low-Grade Intraepithelial Neoplasia and Endoscopic Resection Specimens

Figure 2

(a) A 20 mm sessile lobulated lesion with erythema and surface unevenness on the rectum. (b) The lesion was excised by endoscopic submucosal dissection. (c) Microscopic features of initial EFB. The biopsy specimen showed mild glandular disarray and stratified epithelial cells with rod-like nuclei. These characteristics were diagnosed with “tubular” low-grade intraepithelial neoplasm (H&E, original magnification ×4). (d) Microscopic features of initial EFB (H&E, original magnification ×20). (e) Microscopic features of ER specimen. The glandular structure on the left side is severely distorted and fused by marked proliferation of disarrayed glands, and epithelial cells showed enlarged and irregular nuclei with nucleoli. These characteristics were consistent with moderately differentiated adenocarcinoma with submucosal invasion (H&E, original magnification ×4). No residual was observed in the tumor margin and base. (f) Microscopic features of ER specimen (H&E, original magnification ×20).

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