Table 2. Baseline characteristics of included patients in the study (2,997 patients).
| Parameters | Number (%) |
|---|---|
| Age (years) | |
| <40 | 109 (3.6) |
| 40–69 | 1,700 (56.7) |
| ≥70 | 1,188 (39.6) |
| Race | |
| White | 2,315 (77.2) |
| Black | 500 (16.7) |
| Others | 173 (5.8) |
| Unknown | 9 (0.3) |
| Gender | |
| Male | 1,644 (54.9) |
| Female | 1,353 (45.1) |
| Sub-site | |
| Duodenum | 1,343 (44.8) |
| Jejunum | 633 (21.1) |
| Ileum | 545 (18.2) |
| Meckel’s diverticulum | 5 (0.2) |
| Overlapping lesion | 38 (1.3) |
| Small intestine, NOS | 433 (14.4) |
| Diagnosis | |
| Histology/cytology | 2,994 (99.9) |
| Unknown | 3 (0.1) |
| Grade | |
| I | 267 (8.9) |
| II | 1,556 (51.9) |
| III | 1,000 (33.4) |
| IV | 44 (1.5) |
| Unknown | 130 (4.3) |
| Surgical treatment | |
| Radical surgery | 2,816 (94.0) |
| No radical surgery | 127 (4.2) |
| Unknown | 54 (1.8) |
| Lymph node ratio, mean (standard deviation) | 0.20 (0.29) |
| AJCC stage groups 6th edition* | |
| I | 279 (9.3) |
| II | 1,026 (34.2) |
| III | 1,182 (39.4) |
| IV | 510 (17.0) |
| AJCC stage groups 7th edition | |
| I | 279 (9.3) |
| IIA | 638 (21.3) |
| IIB | 388 (12.9) |
| IIIA | 772 (25.8) |
| IIIB | 410 (13.7) |
| IV | 510 (17.0) |
| AJCC stage groups 8th edition | |
| I | 279 (9.3) |
| IIA | 638 (21.3) |
| IIB | 388 (12.9) |
| IIIA | 578 (19.3) |
| IIIB | 604 (20.2) |
| IV | 510 (17) |
| Staging approach | |
| Pathological | 2,801 (93.5) |
| Clinical | 108 (3.6) |
| Unknown | 88 (2.9) |
| Distant metastases* | |
| Bone | 8 (0.3) |
| Brain | 2 (0.1) |
| Liver | 116 (3.9) |
| Lung | 33 (1.1) |
*, for patients diagnosed starting from 2010. AJCC, American Joint Committee on Cancer; NOS, not otherwise specified.