Magnifying Narrow Band Imaging (NBI) for the Diagnosis of Localized Colorectal Lesions Using the Japan NBI Expert Team (JNET) Classification

Abstract

were compared with the final pathological diagnoses to determine the JNET classification's accuracy. The interobserver agreement was calculated, and the intraobserver agreement was assessed after 6 months. Results: The final pathological diagnoses identified 14 HPs/SSPs, 127 LGDs, 22 HGDs, 19 SM-s carcinomas, and 17 SM-d carcinomas. The respective sensitivities, specificities, positive predictive value, negative predictive value, and accuracies were as follows: Type 1, 85.7, 99.5, 92.3, 98.9, and 98.5%; Type 2A, 96.0, 81.9, 90.3, 92.1, and 90.9%; Type 2B, 75.6%, 90.5, 67.3, 93.4, and 87.4%; and Type 3, 29.4%, 100, 100, 93.8, and 94.0%. The interobserver agreement and the intraobserver agreement were moderate (κ value: 0.52) and excellent (κ value: 0.88), respectively. Lesions presenting as Type 2B during NBI comprised a range of colorectal tumors, including HGDs, SM-s, and SM-d. Conclusions: The JNET classification was useful for the diagnosis of HPs/SSPs, LGDs, and SM-d, but not SM-s lesions. For low-confidence cases, magnified chromoendoscopy is recommended to ensure correct diagnoses. In this classification system, types 1, 2A, 2B, and 3 correspond to hyperplastic polyps (HPs) including sessile serrated polyps (SSPs), low-grade dysplasia (LGD), high-grade dysplasia (HGD) to shallow submucosal invasive (SM-s) carcinomas, and deep submucosal invasive (SM-d) carcinomas, respectively. Methods: To validate this system, we performed a retrospective image evaluation study, in which 199 colorectal tumors previously assessed by NBI magnifying endoscopy were classified by 3 blinded experienced colonoscopists using the JNET system. The results

Endoscopic Diagnostic Support System for cT1b Colorectal Cancer Using Deep Learning

“…For that reason, for accurate depth of invasion diagnoses, chromoendoscopies using pigment are used when making observations under white light [25,28]. Furthermore, with the development of the endoscopic modality, observations using magnified endoscopies and NBI as well as the combination with endoscopic ultrasonography are used for observing pit patterns on the surface of colon lesions [24,26,29,30]. Endoscopic ultrasonography is useful for depth of invasion diagnoses, with an accuracy rate of 81.0%; however, there is no significant difference in accuracy rates compared to other methods, with 81.5% for conventional light colon endoscopy and 82.1% for magnification endoscopy.…”

Endoscopic Treatment of Solitary Colonic Ganglioneuroma

“…We used magnified NBI and the Japan NBI Expert Team classification to determine that the polyp was consistent with Type 1 (Fig. 1c) [6]. Because this finding was consistent with a sessile serrated adenoma/polyp or hyperplastic polyp, we performed a diagnostic endoscopic mucosal resection, with no complications.…”

An International Study on the Diagnostic Accuracy of the Japan Narrow-Band Imaging Expert Team Classification for Colorectal Polyps Observed with Blue Laser Imaging

“…However, several different classifications were proposed, leading to problems such as multiple terms for the same or similar findings, differences in describing the surface pattern, and differences of features between protruding and flat lesions. In June 2016, the Japan NBI Expert Team (JNET) proposed a unified magnifying NBI classification of colorectal tumors, the JNET classification [16], and investigation of its clinical usefulness is currently underway [8,17,18].…”