TABLE 1.
Demographic and clinicopathologic variables
| Variable | SEER (n = 11 006) | CIAH (n = 3521) | PUCHI (n = 1432) | P Value | |||
|---|---|---|---|---|---|---|---|
| n | % | n | % | n | % | ||
| Mean age (y) | 66.9 ± 13.6 | 60.3 ± 11.2 | 61.7 ± 11.7 | <.001 | |||
| Sex | <.001 | ||||||
| Male | 6353 | 57.7 | 2371 | 67.3 | 997 | 69.6 | |
| Female | 4653 | 42.3 | 1150 | 32.7 | 435 | 30.4 | |
| Race | |||||||
| Non‐Latino White | 4188 | 38.1 | |||||
| Latino‐White | 2265 | 20.6 | |||||
| Black | 1700 | 15.4 | |||||
| Chinese | 591 | 5.4 | 1432 | 100 | |||
| Japanese | 472 | 4.3 | 3521 | 100 | |||
| Korean | 765 | 7 | |||||
| Others | 1025 | 9.3 | |||||
| Tumor location | <.001 | ||||||
| Upper | 1380 | 12.6 | 733 | 20.8 | 311 | 21.7 | |
| Middle | 1233 | 11.2 | 1710 | 48.6 | 294 | 20.5 | |
| Lower | 4397 | 40 | 979 | 27.8 | 761 | 53.1 | |
| Overlapping lesion | 859 | 7.8 | 99 | 2.8 | 66 | 4.6 | |
| Unknown | 3137 | 28.5 | |||||
| Tumor size (cm) | <.001 | ||||||
| <2.6 | 2692 | 24.5 | 1231 | 35 | 478 | 33.4 | |
| 2.6‐6.6 | 5126 | 46.6 | 1730 | 49.1 | 749 | 52.3 | |
| >6.6 | 2010 | 18.3 | 515 | 14.6 | 188 | 13.1 | |
| Diffuse | 219 | 2 | 45 | 1.3 | 17 | 1.2 | |
| Unknown | 959 | 8.7 | |||||
| Gastrectomy type | <.001 | ||||||
| Subtotal | 8530 | 77.5 | 2790 | 79.2 | 911 | 63.6 | |
| Total | 2476 | 22.5 | 731 | 20.8 | 521 | 36.4 | |
| Tumor extension | <.001 | ||||||
| Mucosa | 987 | 9 | 1281 | 36.4 | 197 | 13.8 | |
| Submucosa | 1688 | 15.3 | 954 | 27.1 | 158 | 11 | |
| Proper muscle | 1516 | 13.8 | 395 | 11.2 | 222 | 15.5 | |
| Subserosa | 3973 | 36.1 | 417 | 11.8 | 313 | 21.9 | |
| Serosa | 2329 | 21.2 | 433 | 12.3 | 503 | 35.1 | |
| Adjacent organ invasion | 513 | 4.7 | 41 | 1.2 | 39 | 2.7 | |
| No. of rLN | <.001 | ||||||
| 1‐15 | 6034 | 54.8 | 192 | 5.5 | 84 | 5.9 | |
| 16‐29 | 3575 | 32.5 | 946 | 26.9 | 639 | 44.6 | |
| >29 | 1397 | 12.7 | 2383 | 67.7 | 709 | 49.5 | |
| No. of mLN | <.001 | ||||||
| 0 | 4723 | 42.9 | 2499 | 71 | 604 | 42.2 | |
| 1‐2 | 1982 | 18 | 466 | 13.2 | 239 | 16.7 | |
| 3‐6 | 1940 | 17.6 | 346 | 9.8 | 218 | 15.2 | |
| 7‐15 | 1697 | 15.4 | 178 | 5.1 | 245 | 17.1 | |
| >15 | 664 | 6 | 32 | 0.9 | 126 | 8.8 | |
| MLR | <.001 | ||||||
| 0 | 4723 | 42.9 | 2499 | 71 | 604 | 42.2 | |
| <0.32 | 2842 | 25.8 | 979 | 27.8 | 583 | 40.7 | |
| 0.32‐0.64 | 1735 | 15.8 | 40 | 1.1 | 189 | 13.2 | |
| >0.64 | 1706 | 15.5 | 3 | 0.1 | 56 | 3.9 | |
| Differentiation | <.001 | ||||||
| Differentiated | 3474 | 31.6 | 1657 | 47.1 | 749 | 52.3 | |
| Undifferentiated | 7532 | 68.4 | 1864 | 52.9 | 683 | 47.7 | |
| Histology | <.001 | ||||||
| Adenocarcinoma | 8341 | 75.8 | 2502 | 71.1 | 1028 | 71.8 | |
| Mucinous Adenocarcinoma | 263 | 2.4 | 59 | 1.7 | 71 | 5 | |
| Signet‐ring cell carcinoma | 2402 | 21.8 | 960 | 27.3 | 333 | 23.3 | |
| Lauren type | <.001 | ||||||
| Intestinal | 2974 | 27 | 1716 | 48.7 | 323 | 22.6 | |
| Diffuse | 3231 | 29.4 | 960 | 27.3 | 367 | 25.6 | |
| Mixed | 742 | 51.8 | |||||
| Unspecified | 4801 | 43.6 | 845 | 24 | |||
| TNM 8th stage | <.001 | ||||||
| IA | 760 | 6.9 | 1862 | 52.9 | 263 | 18.4 | |
| IB | 432 | 3.9 | 391 | 11.1 | 143 | 10 | |
| IIA | 713 | 6.5 | 276 | 7.8 | 132 | 9.2 | |
| IIB | 597 | 5.4 | 244 | 6.9 | 191 | 13.3 | |
| IIIA | 825 | 7.5 | 348 | 9.9 | 251 | 17.5 | |
| IIIB | 953 | 8.7 | 173 | 4.9 | 239 | 16.7 | |
| IIIC | 692 | 6.3 | 35 | 1 | 129 | 9 | |
| Cannot be staged | 6034 | 54.8 | 192 | 5.5 | 84 | 5.9 | |
| Median follow‐up time (month) | 29 | 61 | 51 | ||||
Abbreviations: CIAH, Cancer Institute Ariake Hospital; mLN, metastatic lymph nodes; MLR, metastatic lymph nodes ratio; PUCHI, Peking University Cancer Hospital & Institute; rLN, retrieved lymph nodes; SEER, Surveillance, Epidemiology, and End Results.