Table 2.
Pooled hazard ratios for OS and CSS according to subgroup analyses
| Outcome subgroup | Study number | Case number | HR (95%CI)-model | P value | Heterogeneity | |
|---|---|---|---|---|---|---|
| I2 (%) | P | |||||
| OS | 8 | 2255 | 1.81 (1.40–2.35)-random | < 0.001 | 55.5 | 0.028 |
| Country | ||||||
| Japan | 4 | 571 | 1.98 (1.41–2.77)-fixed | < 0.001 | 0 | 0.469 |
| China | 4 | 1684 | 1.76 (1.19–2.59)-random | 0.005 | 75.9 | 0.006 |
| Pathological type | ||||||
| Squamous | 6 | 1949 | 1.73 (1.26–2.38)-random | 0.001 | 65.0 | 0.014 |
| Multiple | 2 | 306 | 2.18 (1.40–3.40)-fixed | 0.001 | 0 | 0.597 |
| Proportion of NAC | ||||||
| 100% | 1 | 149 | 1.15 (0.56–2.69) | 0.715 | ||
| None | 3 | 1261 | 2.02 (1.13–3.62)-random | < 0.001 | 80.7 | 0.006 |
| Others | 4 | 845 | 1.79 (1.32–2.41)-random | < 0.001 | 25.5 | 0.259 |
| Cut-off value | ||||||
| < 0.04 | 4 | 1105 | 1.68 (1.03–2.73)-random | 0.037 | 46.6 | 0.132 |
| ≥ 0.04 | 4 | 1150 | 1.94 (1.41–2.69)-random | < 0.001 | 59.0 | 0.063 |
| CSS | 2 | 259 | 2.61 (1.67–4.06)-fixed | < 0.001 | 0 | 0.748 |
OS overall survival, CSS cancer-specific survival, NAC neoadjuvant chemotherapy, HR hazard ratio, CI confidence interval