TOPLINE:

A withdrawal time of 3 minutes or longer in the proximal colon during screening colonoscopy was associated with higher rates of detection of proximal and flat adenomas and with lower rates of finding missed lesions on repeat exams than a withdrawal time shorter than 3 minutes.

METHODOLOGY:

• Colonoscopy can miss flat adenomas in the proximal colon that are linked to interval colorectal cancer. Researchers examined whether longer inspection of the proximal colon improved detection and reduced missed lesions.
• They retrospectively analyzed medical records of patients who underwent screening colonoscopy at a hospital in South Korea between January 2021 and December 2023, including a subgroup of patients who had repeat colonoscopies.
• Withdrawal time in the proximal colon was calculated using time stamps from colonoscopy images, with polyp removal time excluded. The proximal colon was defined as the cecum, ascending colon, and hepatic flexure.
• Researchers compared detection and miss rates for polyps, adenomas, flat adenomas, and advanced adenomas in patients whose withdrawal times were shorter than 3 minutes vs 3 minutes or longer; miss rates were assessed using repeat colonoscopy data.

TAKEAWAY:

• The analysis included 10,253 patients (mean age, 59.71 years; 59.8% male). The proximal colon withdrawal time was shorter than 3 minutes in 4162 patients (40.6%) and 3 minutes or longer in 6091 patients (59.4%).
• Patients with a withdrawal time of 3 minutes or longer vs shorter than 3 minutes had higher rates of detection of proximal colon adenoma (21.1% vs 17.8%; P < .001), flat adenoma (5.4% vs 4.2%; P = .006), and polyps (25.1% vs 20.1%; P < .001).
• Among patients with repeat colonoscopy, a withdrawal time of 3 minutes or longer vs shorter than 3 minutes was linked to lower miss rates for proximal colon adenoma (12.8% vs 17.9%), flat adenoma (4.0% vs 8.2%), and polyps (16.6% vs 21.7%; P < .05 for all).
• A proximal colon withdrawal time shorter than 3 minutes was associated with increased odds of a missed adenoma (adjusted odds ratio [aOR], 1.381; P = .043) and a missed flat adenoma (aOR, 2.053; P = .018).

IN PRACTICE:

“Sufficient withdrawal time can increase adenoma detection, but realistic withdrawal time is limited; it is important to find the adequate withdrawal time. Therefore, withdrawal time of more than 3 minutes is required in the proximal colon, but additional studies are still needed,” the authors of the study wrote.

SOURCE:

The study was led by Hyeon Min Rim, Chungnam National University School of Medicine, Daejeon, South Korea. It was published online in Digestive Diseases and Sciences.

LIMITATIONS:

The study was single-center and retrospective; thus, the results may not be generalizable. Withdrawal times estimated from image time stamps may not have matched actual times. Miss rates could have been misclassified because lesions on repeat exams were hard to categorize as missed or newly developed.

DISCLOSURES:

The research received funding from Chungnam National University. The authors declared having no competing interests.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.