Copyright
©The Author(s) 2018. Published by Baishideng Publishing Group Inc. All rights reserved.
Prediction of colorectal tumor grade and invasion depth through narrow-band imaging scoring
Yasuhiko Maeyama, Keiichi Mitsuyama, Tetsuhiro Noda, Shiuchiro Nagata, Tsutomu Nagata, Shinichiro Yoshioka, Hikaru Yoshida, Michita Mukasa, Hiroaki Sumie, Hiroshi Kawano, Jun Akiba, Yuko Araki, Tatsuyuki Kakuma, Osamu Tsuruta, Takuji Torimura
Yasuhiko Maeyama, Keiichi Mitsuyama, Tetsuhiro Noda, Shiuchiro Nagata, Tsutomu Nagata, Shinichiro Yoshioka, Hikaru Yoshida, Michita Mukasa, Hiroaki Sumie, Osamu Tsuruta, Takuji Torimura, Division of Gastroenterology, Department of Medicine, Kurume University School of Medicine, Kurume 830-0011, Japan
Hiroshi Kawano, Department of Gastroenterology, St. Mary’s Hospital, Kurume 830-8543, Japan
Jun Akiba, Department of Diagnostic Pathology, Kurume University Hospital, Kurume 830-0011, Japan
Yuko Araki, Tatsuyuki Kakuma, Biostatistics Center, Kurume University School of Medicine, Kurume 830-0011, Japan
Author contributions: All authors helped to perform the research, read and approved the final manuscript; Maeyama Y, Mitsuyama K, and Tsuruta O contributed to the conception and design of the study. Maeyama Y and Mitsuyama K wrote the manuscript. Maeyama Y, Noda T, Nagata S, Yoshioka S, Yoshida H, Mukasa M, Sumie H, and Kawano H contributed to patient management. Araki Y and Kakuma T analyzed and interpreted the data and performed the statistical analyses. Akiba J and Tsuruta O performed histopathological analysis.
Institutional review board statement: This study was reviewed and approved by the Ethics Committee of the Kurume University Hospital (Japan).
Informed consent statement: As this is a retrospective study, an informed consent waiver was granted by the Ethics Committee of the Kurume University Hospital (Japan). All samples were anonymized and de-identified prior to analysis in order to preserve patient confidentiality. Patients signed an informed consent to treatment.
Conflict-of-interest statement: The authors declare no conflicts of interest.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Keiichi Mitsuyama, MD, PhD, Associate Specialist, Full Professor, Division of Gastroenterology, Department of Medicine, Kurume University School of Medicine, 67 Asahi-machi, Kurume 830-0011, Japan.
ibd@med.kurume-u.ac.jp
Telephone: +81-942-317561 Fax: +81-942-342623
Received: July 3, 2018
Peer-review started: July 4, 2018
First decision: August 25, 2018
Revised: October 19, 2018
Accepted: October 26, 2018
Article in press: October 26, 2018
Published online: November 14, 2018
Processing time: 133 Days and 1.7 Hours
AIM
To determine the usefulness of assigning narrow-band imaging (NBI) scores for predicting tumor grade and invasion depth in colorectal tumors.
METHODS
A total of 161 colorectal lesions were analyzed from 138 patients who underwent endoscopic or surgical resection after conventional colonoscopy and magnifying endoscopy with NBI. The relationships between the surface and vascular patterns of the lesions, as visualized with NBI, and the tumor grade and depth of submucosa (SM) invasion were determined histopathologically. Scores were assigned to distinct features of the surface microstructures of tubular and papillary-type lesions. Using a multivariate analysis, a model was developed for predicting the tumor grade and depth of invasion based on NBI-finding scores.
RESULTS
NBI findings that correlated with a high tumor grade were associated with the “regular/irregular” (P < 0.0001) surface patterns and the “avascular area” pattern (P = 0.0600). The vascular patterns of “disrupted vessels” (P = 0.0714) and “thick vessels” (P = 0.0133) but none of the surface patterns were associated with a depth of invasion of ≥ 1000 μm. In our model, a total NBI-finding score ≥ 1 was indicative of a high tumor grade (sensitivity: 0.97; specificity: 0.24), and a total NBI-finding score ≥ 9 (sensitivity: 0.56; specificity: 1.0) was predictive of a SM invasion depth ≥ 1000 μm. Scores less than these cutoff values signified adenomas and a SM invasion depth < 1000 μm, respectively. Associations were also noted between selected NBI findings and tumor tissue architecture and histopathology.
CONCLUSION
Our multivariate statistical model for predicting tumor grades and invasion depths from NBI-finding scores may help standardize the diagnosis of colorectal lesions and inform therapeutic strategies.
Core tip: While magnifying endoscopy with narrow-band imaging (NBI) has been integrated into diagnostic histopathology, universal standardized criteria for differentiating non-neoplastic lesions, benign adenomas, and malignant neoplasms using NBI are urgently needed. We propose a multivariate statistical model for predicting the tumor grade and invasion depth from NBI finding scores. A total NBI-finding score ≥ 1 is indicative of a high tumor grade (sensitivity: 0.97; specificity: 0.24), while a score ≥ 9 (sensitivity: 0.56; specificity: 1.0) is predictive of a submucosa invasion depth ≥ 1000 μm. Our model may help to standardize the diagnosis of colorectal lesions and inform therapeutic strategies.
