New-generation endocytoscopy for optical characterization of elevated-type early gastric cancer

Narrow-band imaging with magnification is a tool often used to predict the histology of early depressed-type gastric cancer on the basis of the observation of the vascular and surface structure [1]. However, it can be relatively difficult to characterize elevated-type lesions because the alert signs, such as microvascular pattern or demarcation line, are sometimes obscure [2]. New-generation endocytoscopy (single lens, continuous zoom) enables in vivo ultrahigh magnification (× 520) for direct visualization at the cellular level and allows a precise pathological prediction of gastrointestinal neoplasia [3]. Herein, we report two patients with gastric elevated lesions that were characterized accurately by endocytoscopy ([Video 1]).

Video 1 Endocytoscopy with CM double staining (1 % methylene blue and 0.05 % crystal violet) to characterize two elevated-type gastric lesions. The first case showed some enlarged, disarranged, hyperchromatic nuclei, with complete distortion of the glandular structure, consistent with gastric cancer. The second case revealed a regularly arranged glandular structure with sparse small round nuclei, which was recognized as being a benign lesion.

Patient 1 An 80-year-old man was referred for endoscopic examination because of intermittent epigastralgia. One 2-cm elevated lesion was found on the posterior wall of gastric antrum using conventional white-light endoscopy ([Fig. 1 a]) and narrow-band imaging ([Fig. 1 b]). Prior to endocytoscopic observation, a mixture of 1 % methylene blue and 0.05 % crystal violet (CM double staining) was sprayed over the lesion to stain the nuclei and cytoplasm. Endocytoscopy showed some enlarged, disarranged, hyperchromatic nuclei (“enlarged nuclear sign”), with complete distortion of the glandular structure, features which are consistent with gastric cancer ([Fig. 1 c]) [4]. Endoscopic submucosal dissection (ESD) was performed, with histopathology revealing a well-differentiated adenocarcinoma with invasion of the muscularis mucosa ([Fig. 1 d]).

Fig. 1 Images from patient 1 showing: a a 2-cm elevated lesion on the posterior wall of the gastric antrum on conventional white-light endoscopy; b the same lesion on narrow-band imaging; c some enlarged, disarranged, hyperchromatic nuclei (enlarged nuclear sign), with complete distortion of the glandular structure on endocytoscopy; d a well-differentiated adenocarcinoma with invasion of the muscularis mucosa on histopathology of the endoscopic submucosal dissection specimen.

Patient 2 A 52-year-old man underwent endoscopic examination for longstanding acid regurgitation. A 2-cm elevated lesion was found accidentally on the posterior wall of the prepyloric antrum on endoscopy ([Fig. 2 a, b]). Endocytoscopy was performed after CM double staining and showed a regularly arranged glandular structure, with sparse small round nuclei, which was recognized as being a benign lesion ([Fig. 2 c]). ESD was performed, and the histopathology revealed a hyperplastic polyp ([Fig. 2 d]).

Fig. 2 Images from patient 2 showing: a a 2-cm elevated lesion on white-light endoscopy; b the same lesion on narrow-band imaging; c a regularly arranged glandular structure with sparse small round nuclei on endocytoscopy; d a hyperplastic polyp on histopathology of the endoscopic resection specimen.

Endocytoscopy is therefore useful for real-time optical biopsy to distinguish early gastric cancer from non-cancerous lesions.

Endoscopy_UCTN_Code_CCL_1AB_2AD_3AB

Publication History

Article published online:
28 September 2021

• References

• 1 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.e3
• 2 Yao K, Iwashita A, Tanabe H. et al. White opaque substance within superficial elevated gastric neoplasia as visualized by magnification endoscopy with narrow-band imaging: a new optical sign for differentiating between adenoma and carcinoma. Gastrointest Endosc 2008; 68: 574-580
• 3 Abad MRA, Shimamura Y, Fujiyoshi Y. et al. Endocytoscopy: technology and clinical application in upper gastrointestinal tract. Transl Gastroenterol Hepatol 2020; 5: 28
• 4 Abad MRA, Inoue H, Ikeda H. et al. Utilizing fourth-generation endocytoscopy and the 'enlarged nuclear sign' for in vivo diagnosis of early gastric cancer. Endosc Int Open 2019; 7: E1002-E1007