Impact of the clinical use of artificial intelligence-assisted neoplasia detection for colonoscopy: a large-scale prospective, propensity score-matched study (with video).

BACKGROUND AND AIMS: Recently, the use of computer-aided detection (CADe) for colonoscopy has been investigated to improve the adenoma detection rate (ADR). We aimed to assess the efficacy of a regulatory-approved CADe in a large-scale study with high numbers of patients and endoscopists. METHODS: This was a propensity score-matched prospective study that took place at a university hospital between July 2020 and December 2020. We recruited patients aged ≥20 years who were scheduled for colonoscopy. Patients with polyposis, inflammatory bowel disease, or incomplete colonoscopy were excluded. We used a regulatory-approved CADe system and conducted a propensity score matching-based comparison of the ADR between patients examined with and without CADe as the primary outcome. RESULTS: During the study period, 2261 patients underwent colonoscopy with the CADe system or routine colonoscopy, and 172 patients were excluded in accordance with the exclusion criteria. Thirty endoscopists (9 nonexperts and 21 experts) were involved in this study. Propensity score matching was conducted using 5 factors, resulting in 1836 patients included in the analysis (918 patients in each group). The ADR was significantly higher in the CADe group than in the control group (26.4% vs 19.9%, respectively; relative risk, 1.32; 95% confidence interval, 1.12-1.57); however, there was no significant increase in the advanced neoplasia detection rate (3.7% vs 2.9%, respectively). CONCLUSIONS: The use of the CADe system for colonoscopy significantly increased the ADR in a large-scale prospective study including 30 endoscopists (Clinical trial registration number: UMIN000040677.).

Effect of green tea extract on reactive oxygen species produced by neutrophils from cancer patients.

BACKGROUND/AIM: Oxidative stress in cancer patients has been demonstrated to be partly mediated by neutrophils. Although it is reported that natural antioxidants, such as green tea extract, reduce oxidative stress, there is limited evidence of their effects in cancer patients. This study aimed to determine the effect of green tea extract on reactive oxygen species produced by neutrophils from cancer patients. MATERIALS AND METHODS: Peripheral blood samples were obtained from eighteen patients with advanced cancer. Green tea extract was added to the blood samples with luminol on Mebiol gel, and luminol-dependent chemiluminescence was measured to monitor the production of reactive oxygen species from migrated neutrophils into the gel, at 37°C. RESULTS: Luminol-dependent chemiluminescence was significantly down-regulated in the presence of green tea extract in a concentration-dependent manner. CONCLUSION: These results indicate the antioxidant effect of green tea extract on reactive oxygen species produced by neutrophils, which may be effective in reducing oxidative stress in cancer patients.