Prospective Study
Copyright ©The Author(s) 2018. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Oncol. Apr 15, 2018; 10(4): 96-102
Published online Apr 15, 2018. doi: 10.4251/wjgo.v10.i4.96
Prospective real-time evaluation of diagnostic performance using endocytoscopy in differentiating neoplasia from non-neoplasia for colorectal diminutive polyps (≤ 5 mm)
Takahiro Utsumi, Yasushi Sano, Mineo Iwatate, Hironori Sunakawa, Akira Teramoto, Daizen Hirata, Santa Hattori, Wataru Sano, Noriaki Hasuike, Kazuhito Ichikawa, Takahiro Fujimori
Takahiro Utsumi, Yasushi Sano, Mineo Iwatate, Hironori Sunakawa, Akira Teramoto, Daizen Hirata, Santa Hattori, Wataru Sano, Noriaki Hasuike, Gastrointestinal Center and Institute of Minimally Invasive Endoscopic Care (iMEC), Sano Hospital, Hyogo 655-0031, Japan
Kazuhito Ichikawa, Takahiro Fujimori, Department of Pathology, Shinko Hospital, Hyogo 651-0072, Japan
Author contributions: Utsumi T, Sano Y, Iwatate M, Sunakawa H, Teramoto A, Hirata D, Sano W, Hasuike N, Ichikawa K and Fujimori T designed the study; Utsumi T collected the data; Utsumi T, Sano Y and Iwatate M drafted the study, analyzed the data and wrote the manuscript.
Institutional review board statement: This study was approved by the Institutional Review Board at Sano Hospital.
Informed consent statement: Written informed consent for the procedures was obtained from all patients.
Conflict-of-interest statement: None.
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: Yasushi Sano, MD, PhD, Doctor, Professor, Gastrointestinal Center and Institute of Minimally Invasive Endoscopic Care (iMEC), Sano Hospital, 2-5-1 Shimizugaoka, Tarumi-ku, Hyogo 655-0031, Japan. ys_endoscopy@hotmail.com
Telephone: +81-78-7851000 Fax: +81-78-7850077
Received: December 17, 2017
Peer-review started: December 17, 2017
First decision: January 6, 2018
Revised: January 10, 2018
Accepted: March 6, 2018
Article in press: March 6, 2018
Published online: April 15, 2018
Processing time: 120 Days and 6 Hours
Abstract
AIM

To clarify the diagnostic performance of endocytoscopy for differentiation between neoplastic and non-neoplastic colorectal diminutive polyps.

METHODS

Patients who underwent endocytoscopy between October and December 2016 at Sano Hospital were prospectively recruited. When diminutive polyps (≤ 5 mm) were detected, the lesions were evaluated by endocytoscopy after being stained with 0.05% crystal violet and 1% methylene blue. The diminutive polyps were classified into five categories (EC 1a, 1b, 2, 3a, and 3b). Endoscopists were asked to take a biopsy from any lesion diagnosed as EC1b (indicator of hyperplastic polyp) or EC2 (indicator of adenoma). We have assessed the diagnostic performance of endocytoscopy for EC2 and EC1b lesions by comparison with the histopathology of the biopsy specimen.

RESULTS

A total of 39 patients with 63 diminutive polyps were analyzed. All polyps were evaluated by endocytoscopy. The mean polyp size was 3.3 ± 0.9 mm. Among the 63 diminutive polyps, 60 were flat and 3 were pedunculated. The mean time required for EC observation, including the time for staining with crystal violet and methylene blue, was 3.0 ± 1.9 min. Histopathologic evaluation showed that 13 polyps were hyperplastic and 50 were adenomas. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of EC2 for adenoma compared with EC1b for hyperplastic polyp were 98.0%, 92.3%, 96.8%, 98.0% and 92.3%, respectively. There were only two cases of disagreement between the endoscopic diagnosis made by endocytoscopy and the corresponding histopathological diagnosis.

CONCLUSION

Endocytoscopy showed a high diagnostic performance for differentiating between neoplastic and non-neoplastic colorectal diminutive polyps, and therefore has the potential to be used for “real-time histopathology”.

Keywords: Endocytoscopy; Diagnostic performance; Diminutive polyp; Endocytoscopic classification; Real-time histopathology

Core tip: Single-Charge Coupled Device integrated type endocytoscopy (OLYMPUS, Japan) is going to be newly launched in 2018. Endocytoscopy with approximately 500-fold magnification capability allows us to observe both structural and cellular atypia in vivo, and is expected to be used as an optical biopsy. In our prospective study, we aimed to clarify the diagnostic performance of endocytoscopy in differentiating neoplasia from non-neoplasia for colorectal diminutive polyps (≤ 5 mm). The diagnostic performance of endocytoscopy met the threshold of the Preservation and Incorporation of Valuable endoscopic Innovations statement for “resect-and-discard” and “diagnose-and-leave” strategies.