Table 3.
Cox proportional hazards regression models for OS
| Characteristic | Univariate analysis | Multivariable model | ||
|---|---|---|---|---|
| HR (95% CI) | p value | HR (95% CI) | p value | |
| Agea | .404 | — | ||
| 51 | Ref | — | ||
| 70 | 0.88 (0.65–1.19) | |||
| Gender | .483 | — | ||
| Female | Ref | — | ||
| Male | 0.17 (0.75–1.81) | |||
| Site | .754 | — | ||
| Gastric body or antrum | Ref | — | ||
| Gastroesophageal junction | 1.07 (0.70–1.65) | |||
| Histotype | .200 | — | ||
| Intestinal | Ref | — | ||
| Diffuse | 1.45 (0.92–2.30) | |||
| Mixed |
1.50 (0.68–3.32) |
|||
| HER2 status | .866 | — | ||
| Positiveb | Ref | — | ||
| Negative | 1.04 (0.64–1.69) | |||
| Time to metastases | .084 | — | ||
| Metachronous | Ref | — | ||
| Synchronous | 1.71 (0.93–3.15) | |||
| Primary tumor resected | .002 | .004 | ||
| Yes | Ref | Ref | ||
| No | 2.05 (1.31–3.19) | 1.97 (1.24–3.11) | ||
| Number of metastatic sites | .033 | .181 | ||
| 1 | Ref | Ref | ||
| >1 | 1.56 (1.04–2.36) | 1.34 (0.87–2.04) | ||
| Liver metastases | .662 | — | ||
| No | Ref | — | ||
| Yes | 1.10 (0.71–1.72) | |||
| Peritoneal metastases | .089 | — | ||
| No | Ref | — | ||
| Yes | 1.43 (0.95–2.16) | |||
| MSI status | .610 | — | ||
| MSI‐low/MSS | Ref | — | ||
| MSI‐high | 1.22 (0.56–2.65) | |||
| EBV status | .035 | .038 | ||
| Negative | Ref | Ref | ||
| Positive | 0.12 (0.02–0.86) | 0.12 (0.02–0.89) | ||
a
The values represent the first and third quartile, respectively, of the variable distribution.
b
HER2‐positive cases were defined as those with a score of 3+ at immunohistochemical staining (IHC) or IHC 2+ and amplified at the fluorescence in situ hybridization test.
Abbreviations: —, not applicable; CI, confidence interval; EBV, Epstein‐Barr virus; HER2, human epidermal growth factor receptor 2; HR, hazard ratio; MSI, microsatellite instability; MSS, microsatellite stable.