Table 1.
Application of artificial intelligence in endoscopic detection of early esophageal cancer
| Ref. | Modality | AI technique | No. of images/cases in training dataset (positive/negative) | No. of images/cases in test dataset (positive/negative) | Results |
| van der Sommen et al[14], 2016 | HD-WLE | SVM | 100 (60 early BE neoplasia/40 BE) | 100 (60 early BE neoplasia/40 BE) | Sensitivity 83%/specificity 83% |
| de Groof et al[15], 2019 | HD-WLE | SVM | 60 (40 early BE neoplasia/20 BE) | 60 (40 early BE neoplasia/20 BE) | Sensitivity 95%/specificity 85% |
| Ebigbo et al[16], 2019 | HD-WLE | CNN | 100 (50 early BE neoplasia/50 BE) | 100 (50 early BE neoplasia/50 BE) | Sensitivity 92%/specificity 100% |
| Ebigbo et al[16], 2019 | HD-WLE/NBI | CNN | 148 (early BE neoplasia/BE) | 148 (early BE neoplasia/BE) | HD-WLE sensitivity 97%/specificity 88%; NBI sensitivity 94%/specificity 80% |
| Hashimoto et al[17], 2020 | WLE/NBI | CNN | 1374 (early BE neoplasia/BE) | 253 WLE (146 early BE neoplasia/107 BE) 205 NBI (79 early BE neoplasia/126 BE) | WLE sensitivity 98.6%/specificity 88.8%; NBI sensitivity 92.4%/specificity 99.2% |
| de Groof et al[18], 2020 | HD-WLE | ResNet-UNet | 1247 WLE + 297 HD-WLE (early BE neoplasia/BE) | 80 (40 early BE neoplasia/40 BE) | Sensitivity 90%/specificity 88% |
| Swager et al[22], 2017 | VLE | SVM | 60 (30 early BE neoplasia/30 BE) | 60 (30 early BE neoplasia/30 BE) | Sensitivity 90%/specificity 93% |
| Veronese et al[20], 2013 | CLE | SVM | 337 (23 GM/263 IM/51 neoplasia) | 337 (23 GM/263 IM/51 neoplasia) | Sensitivity 96%/95%/100% |
| Ghatwary et al[23], 2019 | CLE | SVM | 262 (GM/IM/neoplasia) | 262 (GM/IM/neoplasia) | Sensitivity 70%/93%/93% |
| Hong et al[24], 2017 | CLE | CNN | 236 (26 GM/155 IM/55 neoplasia) | 26 (4 GM/17 IM/5 neoplasia) | Sensitivity 0%/100%/80% |
| Ebigbo et al[25], 2020 | HD-WLE | CNN | 129 (early BE neoplasia/BE) | 62 (36 early BE neoplasia/26 BE) | Sensitivity 83.7%/specificity 100% |
| Cai et al[26], 2019 | WLE | CNN | 2428 (1332 early ESCC/1096 healthy control) | 187 (91 early ESCC/96 healthy control) | Sensitivity 97.8%/specificity 85.4% |
| Ohmori et al[27], 2020 | WLE/NBI | Single Shot MultiBox Detector | 22562 (17435 superficial ESCC/5127 control) | 727 (255 WLE/268 non-magnifying NBI/204 magnifying NBI) | WLE sensitivity 90%/specificity 76%; non-magnifying NBI sensitivity 100%/specificity 63%; magnifying NBI sensitivity 98%/specificity 56% |
| Zhao et al[31], 2019 | Magnifying NBI | Double-labeling fully convolutional network | 1383 (207 type A IPCL/970 type B1 IPCL/206 type B2 IPCL) | 1383 (207 type A IPCL/970 type B1 IPCL/206 type B2 IPCL) | Sensitivity 71.5%/91.1%/83.0% |
| Nakagawa et al[32], 2019 | WLE/NBI | CNN | 8660 non-magnifying (7230 EP-SM1/1430 SM2/3); 5678 magnifying (4916 EP-SM1/762 SM2/3) | 914 (405 non-magnifying/509 magnifying) | Non-magnifying sensitivity 95.4%/specificity 79.2%; magnifying sensitivity 91.6%/specificity 79.2% |
| Tokai et al[33], 2020 | WLE/NBI | CNN | 1751 superficial ESCC | 291 (201 EP-SM1/90 SM2) | Sensitivity 84.1%/specificity 73.3% |
| Shin et al[36], 2015 | HRME | Two-class linear discriminant analysis | 104 (15 early ESCC/89 control) | 167 (19 early ESCC/148 control) | Sensitivity 84%/specificity 95% |
| Quang et al[37], 2016 | HRME | Two-class linear discriminant analysis | 104 (15 early ESCC/89 control) | 3 (1 early ESCC/2 control) | Sensitivity 100%/specificity 100% |
| Everson et al[38], 2019 | magnifying NBI | CNN | 7046 sequential images (squamous cell neoplasia/healthy control) | 7046 sequential images (squamous cell neoplasia/healthy control) | Sensitivity 89.7%/specificity 96.9% |
| Guo et al[39], 2020 | NBI | SegNet | 6473 (early ESCC/control) | 47 (27 non-magnifying videos/20 magnifying videos) | Non-magnifying NBI sensitivity 60.8%; magnifying NBI sensitivity 96.1% |
AI: Artificial intelligence; EC: Esophageal cancer; HD-WLE: High-definition white light endoscopy; SVM: Support vector machine; BE: Barrett's esophagus; CNN: Convolutional neural network; NBI: Narrow band imaging; VLE: Volumetric laser endomicroscopy; CLE: Confocal laser endomicroscopy; GM: Gastric metaplasia; IM: Intestinal metaplasia; ESCC: Esophageal squamous cell carcinoma; IPCL: Intrapapillary capillary loop; EP-SM1: Epithelium-submucosal cancers invading up to 200 μm; HRME: High-resolution microendoscopy.