Predictive value of mucosal vascular pattern under narrow-band imaging colonoscopy in colonic epithelial proliferation of patients with ulcerative colitis / 中华消化杂志

ABSTRACT

Objective:To investigate the predictive value of mucosal vascular pattern (MVP) in colonic epithelial proliferation of patients with ulcerative colitis (UC) under narrow-band imaging (NBI) colonoscopy.Methods:From December 1, 2012 to January 31, 2015, 42 patients with UC visiting Peking Union Medical College Hospital and receiving NBI colonoscopy were selected. The images of 119 colorectal lesions of all the patients under the conventional white light and NBI endoscopy were collected and at least one biopsy of each lesion was obtained for histological assessment. All the endoscopic images were randomly allocated to one endoscopist (associated chief physician) for the MVP and the Mayo endoscopic score (MES) assessment. The degree of mucosal inflammation was graded from 0 to 4 according to the histological colitis score. The degree and distribution of Ki-67 expression were evaluated by immunohistochemical staining. Student-Newman-Keuls (SNK)- q test and Spearman rank correlation analysis were used for statistical analysis. Results:Under NBI colonoscopy, the MVP of patients with UC was divided into clear type, obscure type and absent type. According to the morphology of mucosal glandular duct, the absent type was divided into crypt opening subtype and villous subtype. There was a positive correlation between MVP under NBI mode and the MES under white light mode ( r=0.80, P<0.001). The Ki-67 staining indexes of MVP obscure type, absent type, crypt opening subtype and villous subtype of absent type were all higher than that of MVP clear type (30.3±12.8, 45.9±12.5, 45.5±12.1 and 46.3±13.1 vs. 15.6±7.3), and the differences were statistically significant (SNK- q test, all P<0.001); and the Ki-67 staining indexes of MVP absent type, crypt opening subtype and villous subtype of MVP absent type were all higher than that of MVP obscure type, and the differences were statistically significant (SNK- q test, all P<0.001). There was a positive correlation between the MVP type under NBI colonoscopy and the distribution of Ki-67 expression ( r=0.49, P<0.001). The Ki-67 staining indexes of inflammation grade 2, 3 and 4 were higher than that of grade 1 (28.8±10.9, 40.2±11.6 and 49.5±10.3 vs. 17.1±8.4), and the difference was statistically significant (SNK- q test, all P<0.001); the Ki-67 staining indexes of inflammation grade 3 and 4 were higher than that of grade 2, and Ki-67 staining index of inflammation grade 4 was higher than that of grade 3, and the differences were statistically significant (SNK- q test, all P<0.001). The distribution of Ki-67 expression was positively correlated with the degree of histological inflammation ( r=0.56, P<0.001). Conclusions:The MVP under NBI colonoscopy may indirectly predict the colonic epithelial proliferation of patients with UC, which may be closely related to the degree of mucosal inflammation.