Table 1. Baseline characteristics and univariate analysis of 4407 patients with localized small intestinal neuroendocrine tumors.
| Risk Factors | N (%) | 5-year CSS (%) | 10-year CSS (%) | P value a |
|---|---|---|---|---|
| Age | <0.001 | |||
| ≤50yrs | 966(21.9) | 97.3 | 93.0 | |
| >50yrs | 3441(78.1) | 94.3 | 87.0 | |
| Race | 0.227 | |||
| White | 3430(77.8) | 94.9 | 87.3 | |
| Black | 790(17.9) | 94.9 | 93.8 | |
| Others | 136(3.1) | 94.7 | 94.7 | |
| Unknown | 51(1.2) | 92.3 | 92.3 | |
| Gender | 0.306 | |||
| Male | 2286 (51.9) | 96.1 | 91.0 | |
| Female | 2121(48.1) | 96.0 | 88.8 | |
| Marital Status | 0.470 | |||
| Married | 2674(60.4) | 95.6 | 88.3 | |
| Unmarried | 1432(32.5) | 94.1 | 89.0 | |
| Unknown | 301(6.8) | 93.9 | 89.2 | |
| Tumor Location | <0.001 | |||
| Duodenum | 1419 (32.2) | 96.4 | 94.3 | |
| Jejunum | 230 (5.2) | 93.7 | 88.1 | |
| Ileum | 1759(39.9) | 95.7 | 87.9 | |
| NOS | 999(22.7) | 92.2 | 82.2 | |
| Histological type | <0.001 | |||
| Carcinoid | 3588(81.4) | 95.7 | 89.2 | |
| Neuroendocrine | 762(17.3) | 91.7 | 86.9 | |
| Other subtypes b | 57(1.3) | 82.3 | - e | |
| Differentiated grade | <0.001 | |||
| Well differentiated | 3922(89.0) | 96.2 | 89.9 | |
| Moderately differentiated | 309(7.0) | 89.8 | 74.9 | |
| Poorly/undifferentiatedc | 146(3.3) | 74.9 | 71.2 | |
| Unknown | 30(0.7) | 93.3 | 81.7 | |
| Tumor Size d | <0.001 | |||
| ≤2cm | 2553(57.9) | 96.9 | 93.0 | |
| >2cm | 951(21.6) | 93.0 | 81.2 | |
| Unknown | 903(20.5) | 92.0 | 85.2 | |
| T-classification | <0.001 | |||
| 1 | 1575(35.7) | 97.4 | 96.7 | |
| 2 | 667(15.1) | 98.8 | 95.4 | |
| 3 | 1426(32.4) | 93.4 | 82.9 | |
| 4 | 454(10.3) | 90.2 | 75.4 | |
| Unknown | 285(6.5) | 89.1 | 84.8 | |
| N-classification | 0.011 | |||
| N0 | 2193(49.8) | 96.2 | 91.2 | |
| N1 | 1926(43.7) | 94.3 | 85.4 | |
| Unknown | 288(6.5) | 91.8 | 86.6 | |
| Surgery | 0.001 | |||
| none | 499(11.3) | 91.7 | 82.6 | |
| Surgical resected | 3908(88.7) | 95.4 | 89.2 |
Abbreviations: CSS = cancer-specific survival; NOS = not otherwise specified.
a Univariate analysis was calculated by the Kaplan-Meier method with the Log-rank test, P value of <0.05 was considered as statistically significant.
b Other subtypes: neuroendocrine adenocarcinoid, enterochromaffin, goblet, atypical, gastinoma and composite histology.
c Poorly differentiated grade and undifferentiated grade were combined as poor/undifferentiated group because of their limited sample sizes;
d Diameter <=2cm.
e The follow-up time is less than 120 months.