{'fraction_non_alphanumeric': 0.050197405527354765, 'fraction_numerical': 0.025944726452340666, 'mean_word_length': 4.933110367892977, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Endoscopic features of colorectal serrated lesions using image-enhanced endoscopy with pathological analysis

Objective To clarify of the features of sessile serrated adenoma/polyp (SSA/P) observed with image-enhanced endoscopy using immunohistochemical staining. Materials and methods Twenty-five hyperplastic polyps (HP) and 46 SSA/P were studied with autofluorescence imaging (AFI) and magnifying endoscopy with narrow-band imaging (ME-NBI). AFI color change, capillary dilatation, existence of a mucous layer on the tumor surface, and pit dilatation under ME-NBI were examined retrospectively. Immunohistochemical staining was performed with the proliferation-associated antigen MIB-1 (Ki-67). Results Using AFI, a magenta color was observed in 32% of HP and 44% of SSA/P. With NBI observation, capillary dilatation was observed in 4% of HP and 11% of SSA/P, a mucous cap was observed in 60% of HP and 94% of SSA/P, and pit dilatation was observed in 28% of HP and 80% of SSA/P. When magenta color, capillary dilatation, mucous cap, and pit dilatation were used for the differential diagnosis of SSA/P from HP, the sensitivity, specificity, and accuracy were 43, 68, and 52% for AFI, respectively, 10, 96, and, 41% for capillary dilatation, respectively, 94, 40, and 75% for mucous cap, respectively, and 80, 72, and 78% for pit dilatation, respectively. Compared with HP, MIB-1-positive cells were more frequently distributed in the gland’s intermediate zone in SSA/P. Conclusion The biological malignant potential of SSA/P could be higher compared with HP as suggested by the MIB-1 stain. Therefore, endoscopic differentiation of SSA/P from HP is important, and the findings of a mucous cap and dilatated pit might be helpful for the differentiation of SSA/P from HP.