Objective image analysis of non-magnifying image-enhanced endoscopy for diagnosis of small depressed early gastric cancers

Abstract

Background Gastric cancers (GC) after H. pylori eradication are difficult to diagnose even by magnifying narrow-band imaging (NBI) or blue laser imaging (BLI) endoscopy. Little is known with regard to non-magnifying (NM)-NBI/BLI for early GC so we examined the efficacy of NM-NBI/BLI for early GC diagnosis.

Methods We retrospectively analyzed the images of 29 small (≤ 1 cm) intramucosal GC that had been treated with endoscopic submucosal dissection and 137 benign depressed lesions (BDLs). The brightness and shape of the GCs and BDLs by NM-NBI/BLI were assessed with ImageJ software.

Results The NBI/BLI-index, which indicates the brightness of NBI/BLI for visualization, was significantly higher in GC than BDLs in both the H. pylori-infected (P = 0.009) and -eradicated group (P < 0.0001), indicating that GC exhibited brighter colors than the normal surrounding mucosa. The C-index, which refers to the circularity of the lesion, was also significantly higher in GC than BDLs in both H. pylori-infected (P = 0.006) and -eradicated cases (P = 0.004). Based on receiver-operating characteristic curve analysis, cutoff values for the NBI/BLI- and C-indices for GC were 1.04 and 0.58 in the H. pylori-infected cases, and 0.98 and 0.64 in the H. pylori-eradicated cases. With the reference value of the NBI/BLI-index set at ≥ 0.69 with the C-index at ≥ 0.21 in the H. pylori-infected and the NBI/BLI-index at ≥ 0.80 with the C-index at ≥ 0.32 in the H. pylori-eradicated cases, both the sensitivity and negative predictive value for early GC were 100 %. A high NBI/BLI-index tended to be associated with a wide length of the intervening part histologically in the H. pylori-eradicated cases (P = 0.09).

Conclusions The small depressed-type early GC had brighter color and rounder shape compared to BDLs in both H. pylori-infected and -eradicated cases. The NBI/BLI- and C-indices calculated by the image analysis may facilitate identification of small depressed-type GC.

• References

• 1 Correa P. Helicobacter pylori and gastric carcinogenesis. Am J Surg Pathol 1995; 19: S37-S43
• 2 Asaka M, Kato M, Sakamoto N. Roadmap to eliminate gastric cancer with Helicobacter pylori eradication and consecutive surveillance in Japan. J Gastroenterol 2014; 49: 1-8
• 3 IARC Helicobacter pylori Working Group. Helicobacter pylori eradication as a strategy for preventing gastric cancer. IARC Working Group Reports, Vol. 8. Lyons, France: International Agency for Research on Cancer; 2014
• 4 Take S, Mizuno M, Ishiki K. et al. The long-term risk of gastric cancer after the successful eradication of Helicobacter pylori. J Gastroenterol 2011; 46: 318-324
• 5 Kodama M, Murakami K, Okimoto T. et al. Histological characteristics of gastric mucosa prior to Helicobacter pylori eradication may predict gastric cancer. Scand J Gastroenterol 2013; 48: 1249-1256
• 6 Nakayoshi T, Tajiri H, Matsuda K. et al. Magnifying endoscopy combined with narrow band imaging system for early gastric cancer: correlation of vascular pattern with histopathology (including video). Endoscopy 2004; 36: 1080-1084
• 7 Yao K, Anagnostopoulos GK, Ragunath K. Magnifying endoscopy for diagnosing and delineating early gastric cancer. Endoscopy 2009; 41: 462-467
• 8 Ezoe Y, Muto M, Uedo N. et al. Magnifying narrowband imaging is more accurate than conventional white-light imaging in diagnosis of gastric mucosal cancer. Gastroenterology 2011; 141: 2017-2025
• 9 Li HY, Dai J, Xue HB. et al. Application of magnifying endoscopy with narrow-band imaging in diagnosing gastric lesions: a prospective study. Gastrointest Endosc 2012; 76: 1124-1132
• 10 Gotoda T, Saito D, Kondo H. et al. Endoscopic and histological reversibility of gastric adenoma after eradication of Helicobacter pylori. J Gastroenterol 1999; 34 (Suppl. 11) 91-96
• 11 Ito M, Tanaka S, Takata S. et al. Morphological changes in human gastric tumours after eradication therapy of Helicobacter pylori in a short-term follow-up. Aliment Pharmacol Ther 2005; 21: 559-566
• 12 Kobayashi M, Hashimoto S, Nishikura K. et al. Magnifying narrow-band imaging of surface maturation in early differentiated-type gastric cancers after Helicobacter pylori eradication. J Gastroenterol 2013; 48: 1332-1342
• 13 Kitamura Y, Ito M, Matsuo T. et al. Characteristic epithelium with low-grade atypia appears on the surface of gastric cancer after successful Helicobacter pylori eradication therapy. Helicobacter 2014; 19: 289-295
• 14 Hori K, Watari J, Yamasaki T. et al. Morphological characteristics of early gastric neoplasms detected after Helicobacter pylori eradication. Dig Dis Sci 2016; 61: 1641-1651
• 15 Saka A, Yagi K, Nimura S. Endoscopic and histological features of gastric cancers after successful Helicobacter pylori eradication therapy. Gastric Cancer 2016; 19: 524-530
• 16 Kamada T, Hata J, Sugiu K. et al. Clinical features of gastric cancer discovered after successful eradication of Helicobacter pylori: results from a 9-year prospective follow-up study in Japan. Aliment Pharmacol Ther 2005; 21: 1121-1126
• 17 Dohi O, Yagi N, Majima A. et al. Diagnostic ability of magnifying endoscopy with blue laser imaging for early gastric cancer: a prospective study. Gastric Cancer 2017; 20: 297-303
• 18 Bossuyt PM, Reitsma JB, Bruns DE. et al. STARD Group. STARD 2015: an updated list of essential items for reporting diagnostic accuracy studies. BMJ 2015; 351: h5527
• 19 Haruma K, Kato M, Inoue K. et al. Kyoto classification of gastritis. Tokyo: Nihon Medical Center; 2014
• 20 Japanese Gastric Cancer Association. Japanese classification of gastric carcinoma – 3rd English edn. Gastric Cancer 2011; 14: 101-112
• 21 Watari J, Tomita T, Ikehara H. et al. Diagnosis of small intramucosal signet ring cell carcinoma of the stomach by non-magnifying narrow-band imaging: A pilot study. World J Gastrointest Endosc 2015; 7: 1070-1077
• 22 Yagi K, Nozawa Y, Endou S. et al. Diagnosis of early gastric cancer by magnifying endoscopy with NBI from viewpoint of histological imaging: mucosal patterning in terms of white zone visibility and its relationship to histology. Diagn Ther Endosc 2012; 2012: 954809
• 23 Aktepe OC, Ciftçi IH, Safak B. et al. Five methods for detection of Helicobacter pylori in the Turkish population. World J Gastroenterol 2011; 17: 5172-5176
• 24 Akobeng AK. Understanding diagnostic tests 3: Receiver operating characteristic curves. Acta Paediatr 2007; 96: 644-647
• 25 Sharma P, Savides TJ, Canto MI. et al. The American Society for Gastrointestinal Endoscopy PIVI (Preservation and Incorporation of Valuable Endoscopic Innovations) on imaging in Barrett’s esophagus. Gastrointest Endosc 2012; 76: 252-254
• 26 Miyaki R, Yoshida S, Tanaka S. et al. A computer system to be used with laser-based endoscopy for quantitative diagnosis of early gastric cancer. J Clin Gastroenterol 2015; 49: 108-115
• 27 Liu X, Wang C, Bai J. et al. Hue-texture-embedded region-based model for magnifying endoscopy with narrow-band imaging image segmentation based on visual features. Comput Methods Programs Biomed 2017; 145: 53-66
• 28 Kanesaka T, Lee TC, Uedo N. et al. Computer-aided diagnosis for identifying and delineating early gastric cancers in magnifying narrow-band imaging. Gastrointest Endosc 2018; 87: 1339-1344
• 29 Hirasawa T, Aoyama K, Tanimoto T. et al. Application of artificial intelligence using a convolutional neural network for detecting gastric cancer in endoscopic images. Gastric Cancer 2018; 21: 653-660
• 30 Nakamura K. Structure of the gastric cancer. 3rd edn. Tokyo: Igaku-shoin; 2005. (in Japanese)
• 31 Moriyama T, Akiyoshi D, Torisu T. et al. Endoscopic findings of “former early gastric cancer” and “current early gastric cancer”. Early Gastric Cancer 2018. Stomach Intestine 2018; 53: 534-544 Tokyo: Igaku-Shoin (in Japanese)