Table 2.

Characteristics of clinical studies involving computer-aided diagnosis for early esophageal cancer

References	Study design	Target esophageal disease*	Type of specimens for training	Number of specimens for training set	Number of unique patients for training set	Number of specimens for test/validation	Number of unique patients for test/validation
Zhang et al. [28]	Retrospective	SCC, EAC	Endoscopic images*	196,200	–	21,800	–
Mendel et al.[29]	Retrospective	EAC	Endoscopic images	100	39	100	39
Ebigbo et al.[30] (Augsburg data)	Retrospective	EAC	Endoscopic images	148	62	–	–
Ebigbo et al.[30] (MICCAI data)	Retrospective	EAC	Endoscopic images	100	78	–	–
Everson et al.[31]	Retrospective	SCC	Endoscopic images/video	2045	17	812	–
Guo et al. [32]	Retrospective	SCC	Endoscopic images	2085	293	1478	59
Horie et al. [33]	Retrospective	SCC, EAC	Endoscopic images	8428	387	1128	97
Cai et al. [34]	Retrospective	SCC	Endoscopic images	2428	746	187	52
de Groof et al.[26]	Prospective	EAC, BE	Endoscopic images	60	60	–	–
Ghatwary et al.[35]	Retrospective	EAC	Endoscopic images	100	21	–	9
Horie et al. [36]	Retrospective	SCC, EAC	Endoscopic images	8428	384	1118	97
Liu et al. [37]	Retrospective	SCC	Endoscopic images	10,950	503	500	–
Shiroma et al.[38]	Retrospective	SCC, SD, EAC	Endoscopic images	8428	–	40¥	20
Struyvenberg et al. [39]	Retrospective	EAC	Endoscopic images€	1247	–	183	100
Tang et al. [40]	Retrospective	SCC, SD	Endoscopic images	5174	1530	946	280
de Groof et al.[25]	Prospective	EAC	Endoscopic images€	297	95	80	80
Ebigbo et al.[41]	Retrospective	EAC	Endoscopic images	129	–	62	14
Guo et al. [42]	Retrospective	SCC	Endoscopic images	6473	549	6671	880
Ohmori et al.[43]	Retrospective	SCC, SD	Endoscopic images	22,562	–	727	135
de Groof et al.[24]	Prospective	EAC	Endoscopic images (application in live endoscopy)	1544	–	–	160
Hashimoto et al.[44]	Retrospective	EAC	Endoscopic images	1832	100	458	39
Iwagami et al.[45]	Retrospective	EAC-EJ	Endoscopic images	3443	159	275	36

^*1000 patches were made from each endoscopic image, and total number of endoscopic images were 218.

^¥Test/validation was done on 40 test movies of 20 patients.

^€The CAD system was pre-trained on a unique dataset of 494,364 labeled endoscopic images named GastroNet. SCC squamous cell cancer, SD squamous dysplasia, EAC esophageal adenocarcinoma, BE Barrett’s esophagus, EAC-EJ esophageal adenocarcinoma at esophagogastric junction