Table 5.
Comparison of breast cancer-specific survival (BCSS) and overall survival (OS) between matched patients with chemotherapy and no-chemotherapy in specific clinical variables
| Variables | BCSS | OS | ||||
|---|---|---|---|---|---|---|
| Events No | HRs (95%CI) | Pa | Events No | HRs (95%CI) | Pa | |
| T1N1M0 (n = 109) | 21 | 0.666 | 34 | 0.872 | ||
| Chemotherapy | 0.778(0.249–2.432) | 1.072(0.458–2.508) | ||||
| No-Chemotherapy | Reference | Reference | ||||
| T2N0M0 (n = 595) | 80 | < 0.001 | 123 | < 0.001 | ||
| Chemotherapy | 0.420(0.261–0.675) | 0.361(0.243–0.536) | ||||
| No-Chemotherapy | Reference | Reference | ||||
| Stage IIb (n = 283) | 63 | 0.321 | 90 | 0.039 | ||
| Chemotherapy | 0.767(0.454–1.296)* | 0.640(0.419–0.978) | ||||
| No-Chemotherapy | Reference | Reference | ||||
| Grade I&II (n = 546) | 53 | 0.387 | 81 | 0.306 | ||
| Chemotherapy | 0.781(0.445–1.368) | 0.790(0.503–1.240)* | ||||
| No-Chemotherapy | Reference | Reference | ||||
| Grade III (n = 2,114) | 306 | < 0.001 | 461 | < 0.001 | ||
| Chemotherapy | 0.559(0.441–0.708)* | 0.505(0.415–0.615)* | ||||
| No-Chemotherapy | Reference | Reference | ||||
Abbreviation: HR Hazard ratio, CI Confidence interval, BCSS Breast cancer-specific survival, OS Overall survival, Events No Number of events
aP value was adjusted by a multivariate Cox proportional hazard regression model or a time-dependent covariate analysis. Bold type indicates significance
bThe groups using time-dependent covariate analysis were specifically marked with asterisks(*)