Optimized optical stratification by JNET classification with chromoendoscopy for colorectal lesions ≥10 mm

Background
Endoscopic T1b recognition before treatment is crucial for therapeutic decision. We aimed to compare appropriate therapeutic application between Japan NBI Expert Team (JNET) alone and JNET with magnified chromoendoscopy (M-CE) for JNET 2B lesions.
Methods
Superficial colorectal lesions ≥10 mm removed in a Japanese tertiary cancer center between 2016 and 2018 were retrospectively analyzed using a prospectively developed  database. We compared the rate of appropriate therapeutic application, which was defined as surgery for pT1b and advanced cancer, and endoscopic resection for pT1a or less between the following surgery application; strategy1, JNET Type 2B and JNET Type 3, strategy2, JNET Type 3, and strategy3, JNET Type 2B with high-grade V (V_H) pit pattern and JNET Type3.
Results
A total of 1573 lesions, including 56 pT1a, 160 pT1b, and 81 advanced cancers were analyzed. The probability of pT1b or advanced cancers was 1.8%, 30.1%, and 96.6% in JNET Type 2A, 2B, and 3, respectively. By additional M-CE, 359 JNET Type 2B lesions were categorized into non-V (70, 19%), low-grade V (193, 54%), V_H (96, 27%), respectively. The rate of appropriate therapeutic application (95% confidence interval) in strategy 1, 2, and 3 was 83% (81-84), 92% (90-93), and 95% (94-96), respectively.
Conclusions
Initiating JNET application and subsequent magnified chromoendoscopy for JNET Type 2B lesions enables to optimize therapeutic decision for colorectal lesions ≥10 mm.