Artificial intelligence for dysplasia detection during surveillance colonoscopy in patients with ulcerative colitis: A cross-sectional, non-inferiority, diagnostic test comparison study.

BACKGROUND AND STUDY AIM: High-definition virtual chromoendoscopy, along with targeted biopsies, is recommended for dysplasia surveillance in ulcerative colitis patients at risk for colorectal cancer. Computer-aided detection (CADe) systems aim to improve colonic adenoma detection, however their efficacy in detecting polyps and adenomas in this context remains unclear. This study evaluates the CADe Discovery™ system's effectiveness in detecting colonic dysplasia in ulcerative colitis patients at risk for colorectal cancer. PATIENTS AND METHODS: A prospective cross-sectional, non-inferiority, diagnostic test comparison study was conducted on ulcerative colitis patients undergoing colorectal cancer surveillance colonoscopy between January 2021 and April 2021. Patients underwent virtual chromoendoscopy (VCE) with iSCAN 1 and 3 with optical enhancement. One endoscopist, blinded to CADe Discovery™ system results, examined colon sections, while a second endoscopist concurrently reviewed CADe images. Suspicious areas detected by both techniques underwent resection. Proportions of dysplastic lesions and patients with dysplasia detected by VCE or CADe were calculated. RESULTS: Fifty-two patients were included, and 48 lesions analyzed. VCE and CADe each detected 9 cases of dysplasia (21.4% and 20.0%, respectively; p=0.629) in 8 patients and 7 patients (15.4% vs. 13.5%, respectively; p=0.713). Sensitivity, specificity, positive and negative predictive values, and diagnostic accuracy for dysplasia detection using VCE or CADe were 90% and 90%, 13% and 5%, 21% and 2%, 83% and 67%, and 29.2% and 22.9%, respectively. CONCLUSIONS: The CADe Discovery™ system shows similar diagnostic performance to VCE with iSCAN in detecting colonic dysplasia in ulcerative colitis patients at risk for colorectal cancer.

Intestinal ultrasonography and fecal calprotectin for monitoring inflammation of ileal Crohn's disease: two complementary tests.

BACKGROUND/AIMS: Tight control of inflammation and adjustment of treatment if activity persists is the current strategy for the management of Crohn's disease (CD). The usefulness of fecal calprotectin (FC) in isolated involvement of the small intestine in CD is controversial. To assess the usefulness of FC to determine the inflammatory activity detected by intestinal ultrasonography (IUS) in ileal CD. METHODS: Patients with exclusively ileal involvement CD who underwent IUS and an FC were prospectively included. Simple ultrasound index was used to determine inflammatory activity. The usual statistical tests for comparison of diagnostic techniques were used. RESULTS: One hundred and five patients were included, IUS showed inflammatory activity in 59% of patients and complications in 18.1%. FC showed a significant correlation with IUS in the weak range (Spearman coefficient r=0.502; P<0.001); the area under the receiver operating characteristic curve was 0.79 (95% confidence interval, 0.70-0.88; P<0.001). The FC value that best reflected the activity in IUS was 100 µg/g with sensitivity, specificity, and positive and negative predictive values of 73.0%, 71.4%, 79.3% and 63.8%, respectively. There were no differences in FC concentration between patients with or without transmural complications. The addition of serum C-reactive protein to FC did not improve the ability to assess IUS activity. CONCLUSIONS: FC has a significant correlation with IUS to monitor ileal CD activity. This correlation is weak and it does not allow assessing the presence of CD complications. Both tests should be used in conjunction for tight control of ileal CD. More studies on noninvasive tests in this location are needed.

Virtual chromoendoscopy with iSCAN as an alternative method to dye-spray chromoendoscopy for dysplasia detection in long-standing colonic inflammatory bowel disease: a case-control study.

OBJECTIVE: Patients with long-standing colonic inflammatory bowel disease (cIBD) are at increased risk of developing colorectal cancer (CRC). Dye-spray chromoendoscopy (DCE) with targeted biopsies is the preferred technique for surveillance of dysplasia. Virtual chromoendoscopy (VCE) are arising to improve detection rates and adherence to surveillance guidelines, although its role is not yet well defined. The purpose of this study is to assess the effectiveness of VCE with iSCAN as an alternative method for dysplasia detection in cIBD. METHODS: Retrospective case-control study with 191 patients included, 98 in the DCE (Indigo carmine) group and 93 in the VCE (iSCAN, twin-mode 1-3) group. The dysplasia detection and the exploration time were analysed. A logistic regression analysis was performed to ascertain the factors related to colonic dysplasia. RESULTS: A total of 44 dysplastic lesions were detected in 21 (11%) patients. No differences were found in the per lesion and the per patient analysis (dysplastic versus non-dysplastic). Median withdrawal time was shorter in the VCE group than in the DCE group (9 min versus 14 min; p < .001). Location of lesions in the right colon was independently associated with an increased risk for colonic dysplasia (OR = 4.04, 95%CI 1.11-14.65; p = .034) after adjusting for age at inclusion, age at diagnosis, high risk for CRC and Kudo pit pattern. CONCLUSIONS: VCE with iSCAN presents a similar diagnostic performance to conventional DCE in the detection of colonic dysplasia in patients with long-standing cIBD. Furthermore, VCE with iSCAN is a less time-consuming surveillance alternative to DCE.