Comparison of the Diagnostic Accuracy Between Three Dimensional and Standard Colonoscopy of Colorectal Polyps

Summary

Colorectal cancer (CRC) is one of the most common cancers worldwide. These malignancies originate in the colon or rectum, and the majority evolve from pre-existing colonic adenomas (a type of colon polyp). Early detection, identification, and removal of these precancerous lesions can effectively reduce the morbidity and mortality of colorectal cancer.

However, not all colonic polyps possess a significant risk of malignant transformation. Polyps can generally be subdivided into "neoplastic" and "non-neoplastic" lesions; major non-neoplastic polyps include inflammatory polyps, hamartomas, lymphoid polyps, mucosal prolapse polyps, and hyperplastic polyps. On the other hand, neoplastic polyps have the potential to develop into malignancies, primarily including adenomatous polyps and serrated polyps. Adenomatous polyps account for more than 50% of all colonic polyps and are the most common precancerous lesions for CRC. Clinically, they can be further classified into tubular, tubulovillous, or villous adenomas based on histological subtypes. As for serrated polyps, traditional serrated adenomas (TSAs) and sessile serrated lesions (SSLs) possess carcinogenic potential.

During a colonoscopy, detecting colonic polyps is crucial, but it is equally important to identify which polyps have malignant potential. This allows for the accurate resection of true precancerous lesions while avoiding the procedural risks associated with unnecessary polypectomies. Furthermore, in rare instances, diminutive polyps may harbor cancer with deep submucosal invasion. Due to the risks of incomplete resection and lymph node metastasis, such lesions are not suitable for endoscopic resection. Therefore, achieving an accurate endoscopic diagnosis is a key step in determining the most appropriate management strategy for colonic polyps.

To improve the diagnostic accuracy of endoscopy for colonic polyps, multiple modalities have been developed, including careful observation of lesion morphology, as well as various image-enhanced technologies and chromoendoscopy. Meanwhile, three-dimensional (3D) endoscopy, a novel technology, offers superior spatial resolution and depth perception compared to conventional two-dimensional (2D) endoscopy. Studies have confirmed that 3D endoscopy can improve the adenoma detection rate (ADR) due to its enhanced ability to detect flat and inconspicuous lesions. However, whether 3D colonoscopy can also enhance the endoscopic diagnostic accuracy for colonic polyps remains to be explored. Therefore, we designed a randomized controlled trial (RCT) to investigate whether 3D colonoscopy can improve the diagnostic accuracy of colonic polyps compared to conventional 2D colonoscopy.

Conditions

• Colo-rectal Polyps
• Colonoscopy

Interventions

DEVICE

3D MonoStereo

When subjects undergo the colonoscopy, the operator will use the conventional 2D endoscopic mode for insertion. Once the colonoscope reaches the cecum, a research assistant will randomly assign the subject to one of the two endoscopic modality sequences using a sealed envelope, with an expected 1:1 allocation ratio between the two groups. The primary difference between the two groups occurs during the withdrawal of the endoscope from the cecum to the anus. If a polyp lesion is detected, one group will first use conventional 2D imaging for polyp diagnosis, and then switch to 3D endoscopy for a second diagnosis. The other group will do the reverse: completing the diagnosis with 3D endoscopy first, and then switching to conventional 2D endoscopy for a second diagnosis. This design aims to eliminate judgment bias caused by the diagnostic sequence.

Sponsors & Collaborators

• National Taiwan University Hospital

  lead OTHER

Study Design

Allocation

RANDOMIZED

Purpose

DIAGNOSTIC

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2026-05-12

Primary Completion

2027-05-12

Completion

2027-05-12