Efficacy of image-enhanced endoscopy for colorectal adenoma detection: A multicenter, randomized trial

BACKGROUND

Improved adenoma detection at colonoscopy has decreased the risk of developing colorectal cancer. However, whether image-enhanced endoscopy (IEE) further improves the adenoma detection rate (ADR) is controversial.

AIM

To compare IEE with white-light imaging (WLI) endoscopy for the detection and identification of colorectal adenoma.

METHODS

This was a multicenter, randomized, controlled trial. Participants were enrolled between September 2019 to April 2021 from 4 hospital in China. Patients were randomly assigned to an IEE group with WLI on entry and IEE on withdrawal (n = 2113) or a WLI group with WLI on both entry and withdrawal (n = 2098). The primary outcome was the ADR. The secondary endpoints were the polyp detection rate (PDR), adenomas per colonoscopy, adenomas per positive colonoscopy, and factors related to adenoma detection.

RESULTS

A total of 4211 patients (966 adenomas) were included in the analysis (mean age, 56.7 years, 47.1% male). There were 2113 patients (508 adenomas) in the IEE group and 2098 patients (458 adenomas) in the WLI group. The ADR in two group were not significantly different [24.0% vs 21.8%, 1.10, 95% confidence interval (CI): 0.99-1.23, P = 0.09]. The PDR was higher with IEE group (41.7%) than with WLI group (36.1%, 1.16, 95%CI: 1.07-1.25, P = 0.01). Differences in mean withdrawal time (7.90 ± 3.42 min vs 7.85 ± 3.47 min, P = 0.30) and adenomas per colonoscopy (0.33 ± 0.68 vs 0.28 ± 0.62, P = 0.06) were not significant. Subgroup analysis found that with narrow-band imaging (NBI), between-group differences in the ADR, were not significant (23.7% vs 21.8%, 1.09, 95%CI: 0.97-1.22, P = 0.15), but were greater with linked color imaging (30.9% vs 21.8%, 1.42, 95%CI: 1.04-1.93, P = 0.04). the second-generation NBI (2G-NBI) had an advantage of ADR than both WLI and the first-generation NBI (27.0% vs 21.8%, P = 0.01; 27.0% vs 21.2.0%, P = 0.01).

CONCLUSION

This prospective study confirmed that, among Chinese, IEE didn’t increase the ADR compared with WLI, but 2G-NBI increase the ADR.

Prediction of technically difficult endoscopic submucosal dissection for large superficial colorectal tumors: a novel clinical score model

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) is a promising technique for removing superficial GI tumors, but ESD is technically difficult. The aim of this study was to establish a clinical score model for grading technically difficult colorectal ESD.

METHODS

Data on patients, lesions, and outcomes of colorectal ESD at 2 centers were analyzed. The objective parameter of successful ESD within 60 minutes was set as an endpoint to evaluate the difficulty. Independent predictors of difficulty in the derivation cohort were identified by multiple logistic regression analysis and used to develop a clinical score. We validated the score model in the validation cohort.

RESULTS

The clinical score comprised tumor size of 30 to 50 mm (1 point) or ≥50 mm (2 points), at least two-thirds circumference of the lesion (2 points), location in the cecum (1 point), flexure (2 points) or dentate line (1 point), and laterally spreading tumor nongranular lesions (1 point). Areas under the receiver operator characteristic curves for the score model were comparable (derivation [.70] vs internal validation [.69] vs external validation [.69]). The probability of successful ESD within 60 minutes in easy (score = 0), intermediate (score = 1), difficult (score = 2-3), and very difficult (score ≥4) categories were 75.0%, 51.3%, 35.6%, and 3.4% in the derivation cohort; 73.3%, 47.9%, 31.8%, and 16.7% in the internal validation cohort; and 79.5%, 66.7%, 43.3%, and 20.0% in the external validation cohort, respectively.

CONCLUSIONS

This clinical score model accurately predicts the probability of successful ESD within 60 minutes and can be applied to grade the technical difficulty before the procedure.

Self-expandable metallic stenting as a bridge to elective surgery versus emergency surgery for acute malignant right-sided colorectal obstruction

Background

The use of a self-expandable metallic stent (SEMS) as a bridge to surgery has increased for patients with obstructing colorectal cancer. However, relatively few reports have compared SEMS as a bridge to elective surgery for acute malignant obstruction of the right-sided colon (MORC) vs. emergency surgery (ES). This study aimed to evaluate the benefits of elective surgery after SEMS placement vs. ES for patients (including stage IV cases) with acute MORC.

Methods

Patients with acute MORC who underwent radical resection for a primary tumour from July 2008 to November 2016 at Zhongshan Hospital of Fudan University were retrospectively enrolled. Postoperative short-term outcomes, progression-free survival (PFS), and overall survival (OS) were compared between the SEMS and ES groups.

Results

In total, 107 patients with acute MORC (35 in the SEMS group and 72 in the ES group) were included for analysis. The Intensive Care Unit admission rate was lower (11.4% vs. 34.7%, P = 0.011), the incidence of complications was reduced (11.4% vs. 29.2%, P = 0.042), and the postoperative length of hospitalisation was significantly shorter (8.23 ± 6.50 vs. 11.18 ± 6.71 days, P = 0.033) for the SEMS group. Survival curves showed no significant difference in PFS (P = 0.506) or OS (P = 0.989) between groups. Also, there was no significant difference in PFS and OS rates between patients with stage II and III colon cancer. After colectomy for synchronous liver metastases among stage IV patients, the hepatectomy rates for the SEMS and ES groups were 85.7% and 14.3%, respectively (P = 0.029). The hazard ratio for colectomy alone vs. combined resection was 3.258 (95% CI 0.858–12.370; P = 0.041).

Conclusion

Stent placement offers significant advantages in terms of short-term outcomes and comparable prognoses for acute MORC patients. For synchronous liver metastases, SEMS placement better prepares the patient for resection of the primary tumour and liver metastasis, which contribute to improved survival.