Use of endocytoscopy for identification of sessile serrated adenoma/polyps and hyperplastic polyps by quantitative image analysis of the luminal areas

• Main Authors: Yushi Ogawa, Shin-ei Kudo, Yuichi Mori, Nobunao Ikehara, Yasuharu Maeda, Kunihiko Wakamura, Masashi Misawa, Toyoki Kudo, Takemasa Hayashi, Hideyuki Miyachi, Atsushi Katagiri, Fumio Ishida, Haruhiro Inoue
• Format: Article
• Language: English
• Published: Georg Thieme Verlag KG 2017-08-01
• Series: Endoscopy International Open
• Online Access: http://www.thieme-connect.de/DOI/DOI?10.1055/s-0043-113562
• ISSN: 2364-3722; 2196-9736

Background and study aims Recent studies that used magnifying chromoendoscopy and endocytoscopy (EC) to investigate endoscopic features of sessile serrated adenoma/polyps (SSA/Ps) suggested that a dilated crypt opening was an important indicator of SSA/Ps. However, no studies to date have measured the actual extent of dilatation. Hence, we investigated retrospectively the luminal areas using EC to determine a cutoff value for differentiating SSA/Ps from hyperplastic polyps (HPs). Patients and methods A total of 101 lesions, including 25 SSA/Ps, 66 HPs, and 10 normal mucosal samples, assessed by an integrated-type EC were collected. For each lesion, 1 image that showed the widest lumen was selected and the average area of the contiguous 3 lumens were calculated. The cutoff value differentiating SSAPs from HPs was determined by receiver operating curve (ROC) analysis. Results The mean luminal areas of SSA/Ps and HPs were 4152 μm2 and 2117 μm2, respectively. ROC analysis found that a luminal area cutoff of 3068 μm2 had a sensitivity of 80.0 %, a specificity of 77.3 %, an accuracy of 78.0 %, and an area under the ROC curve of 0.865. Furthermore, a cutoff of ≥ 556 μm2 was found to accurately distinguish between HPs and normal mucosa (sensitivity 98.5 %, specificity 100 %, accuracy 98.7 %, and AUC 0.998). Conclusions EC analysis of the luminal area is useful for differentiating between SSAPs and HPs. This approach could be adapted for computer-aided diagnosis of SSA/P.