Table 2. Univariate analyses of OS in the SEER training set.
| Variables | Univariate analysis | |
|---|---|---|
| HR (95% CI) | P value | |
| Age at diagnosis (year) | ||
| ≤44 | Reference | |
| 45–59 | 1.072 (0.119–0.588) | 0.557 |
| 60–74 | 1.315 (0.114–2.408) | 0.016 |
| ≥75 | 2.178 (0.114–6.797) | <0.001 |
| Sex | ||
| Female | Reference | |
| Male | 1.118 (0.052–2.143) | 0.032 |
| Tumor size (cm) | ||
| <3.7 | Reference | |
| 3.7–6.8 | 1.136 (0.059–2.183) | 0.029 |
| >6.8 | 1.105 (0.069–1.442) | 0.149 |
| Prime site of tumor | ||
| Cardia/fundus | Reference | |
| Middle of gastric bodya | 0.694 (0.063–5.814) | <0.001 |
| Antrum/pylorus | 0.768 (0.061–4.338) | <0.001 |
| Tumor number | ||
| <2 | Reference | |
| ≥2 | 1.039 (0.058–0.669) | 0.504 |
| AJCC T stage (8th) | ||
| T1 | Reference | |
| T2 | 1.153 (0.118–1.209) | 0.227 |
| T3 | 1.685 (0.098–5.335) | <0.001 |
| T4 | 2.380 (0.105–8.239) | <0.001 |
| AJCC N stage (8th) | ||
| N0 | Reference | |
| N1 | 1.704 (0.074–7.161) | <0.001 |
| N2 | 2.091 (0.075–9.888) | <0.001 |
| N3a | 2.657 (0.078–12.546) | <0.001 |
| N3b | 3.209 (0.098–11.853) | <0.001 |
| AJCC M stage (8th) | ||
| M0 | Reference | |
| M1 | 1.993 (0.086–8.039) | <0.001 |
| AJCC TNM stage (8th) | ||
| I | Reference | |
| II | – | <0.001 |
| III | – | <0.001 |
| IV | – | <0.001 |
| Liver metastasis | ||
| No | Reference | |
| Yes | 1.221 (0.128–1.568) | 0.117 |
a, middle of gastric body includes body of stomach, lesser curvature of stomach, and greater curvature of stomach. T, N, M stages come from AJCC. AJCC, American Joint Committee on Cancer; SEER, Surveillance, Epidemiology, and End Results.