Clinicopathological characteristics of patients in the derivation and validation cohorts
| Derivation cohort (n=8291) | Validation cohort (n=2029) | P value | |
| Demographics | |||
| Age (years), median (P25 to P75) | 72 (66 to 78) | 73 (67 to 79) | <0.001 |
| Male gender, n (%) | 6182 (74.6) | 1478 (72.8) | 0.112 |
| Comorbidities | |||
| Ischaemic heart disease, n (%) | 567 (6.8) | 163 (8.0) | 0.065 |
| Liver cirrhosis, n (%) | 155 (1.9) | 37 (1.8) | 0.993 |
| CKD with haemodialysis, n (%) | 129 (1.6) | 26 (1.3) | 0.413 |
| Mild/no gastric atrophy, n (%) | 632 (7.6) | 105 (5.2) | <0.001 |
| AT therapy | |||
| Aspirin, n (%) | 793 (9.6) | 188 (9.3) | 0.702 |
| P2Y12RA, n (%) | 344 (4.1) | 116 (5.7) | 0.002 |
| Cilostazol, n (%) | 168 (2.0) | 68 (3.4) | <0.001 |
| Warfarin, n (%) | 255 (3.1) | 71 (3.5) | 0.323 |
| DOAC, n (%) | 189 (2.3) | 64 (3.2) | 0.023 |
| Interruption of AT agents, n (%) | <0.001 | ||
| One kind of agent | 948 (11.4) | 267 (13.2) | |
| Two kinds of agents | 121 (1.5) | 60 (3.0) | |
| Three kinds of agents | 8 (0.1) | 2 (0.1) | |
| Heparin bridging, n (%) | 311 (3.8) | 118 (5.8) | <0.001 |
| Replacement of APAs, n (%) | 85 (1.0) | 36 (1.8) | 0.006 |
| Lesion | |||
| Multiple tumours, n (%) | 1014 (12.2) | 280 (13.8) | 0.056 |
| Location of lower-third, n (%) | 3811 (46.0) | 877 (43.2) | 0.027 |
| Undifferentiated type, n (%) | 445 (5.4) | 61 (3.0) | <0.001 |
| Tumour size (mm), median (P25 to P75) | 15 (9 to 22) | 15 (10 to 23) | <0.001 |
| SM2, n (%) | 528 (6.4) | 127 (6.3) | 0.916 |
| Ulceration (scar), n (%) | 771 (9.3) | 206 (10.2) | 0.254 |
| Procedure | |||
| Procedure time >120 min, n (%) | 1447 (17.5) | 439 (21.6) | <0.001 |
| Piecemeal resection, n (%) | 48 (0.6) | 13 (0.6) | 0.747 |
| Second-look endoscopy, n (%) | 5536 (66.8) | 1848 (91.1) | <0.001 |
| H2 receptor antagonist, n (%) | 3 (0.0) | 2 (0.1) | <0.001 |
| Bleeding, n (%) | 387 (4.7) | 102 (5.0) | 0.487 |
| Hospital stay (day), median (P25 to P75) | 6 (5 to 8) | 7 (5 to 8) | <0.001 |
CKD, chronic kidney disease; AT, antithrombotic; P2Y12RA, P2Y12 receptor antagonist; DOAC, direct oral anticoagulant; APA, antiplatelet agent; SM2, submucosal invasion ≥500 µm from the muscularis mucosa.