Cox proportional hazard rate regression. Ten-year follow-up of ipsilateral breast tumor recurrence (IBTR)
| Variables | No. of IBTRs/no. of patients | Univariable Cox regression | Multivariable Cox regression | ||
| HR (95% CI) | P value | HR (95% CI) | P value | ||
| Combination of immune group and risk group | |||||
| Not activated, low risk | 71/544 | 1.0 | 1.0 | ||
| Not activated, high risk | 35/155 | 2.1 (1.4 to 3.1) | <0.001 | 1.9 (1.3 to 2.9) | 0.002 |
| Activated, low risk | 6/29 | 2.0 (0.87 to 4.6) | 0.105 | 1.8 (0.76 to 4.0) | 0.189 |
| Activated, high risk | 8/96 | 0.68 (0.33 to 1.4) | 0.306 | 0.63 (0.30 to 1.3) | 0.217 |
| Interaction | 0.005* | 0.007* | |||
| Age (cont.) | 120/824 | 0.97 (0.95 to 0.99) | 0.005 | 0.97 (0.96 to 0.99) | 0.003 |
| Tumor size (cont.) | 110/738 | 1.01 (0.97 to 1.04) | 0.761 | – | |
| ER status | |||||
| Negative | 15/94 | 1.0 | – | ||
| Positive | 105/726 | 0.78 (0.46 to 1.35) | 0.376 | – | |
| RT | |||||
| No | 87/437 | 1.0 | 1.0 | ||
| Yes | 33/387 | 0.39 (0.26 to 0.58) | <0.001 | 0.41 (0.27 to 0.61) | <0.001 |
*Likelihood-ratio test.
ER, estrogen receptor; IBTR, ipsilateral breast tumor recurrence; RT, radiotherapy.