Table 3.
Multivariable Cox regression analysis of the association of treatment period with recurrence, stratified by use of radiation in 2558 women with DCIS treated with BCS, controlling for other factors.
| No radiation (N = 1111*)
|
Radiation (N = 1447*)
|
||||||||
|---|---|---|---|---|---|---|---|---|---|
| Variable | N | Events | HR | p-value | N | Events | HR | p-value | |
| Age | Continuous, per year | 1111 | 181 | 0.984 | 0.007 | 1447 | 116 | 0.960 | < 0.0001 |
|
| |||||||||
| Family history | No | 679 | 102 | 1.00 | 887 | 68 | 1.00 | ||
| Yes | 432 | 79 | 1.31 | 0.08 | 560 | 48 | 1.28 | 0.2 | |
|
| |||||||||
| Presentation | Radiologic | 980 | 148 | 1.00 | 1298 | 97 | 1.00 | ||
| Clinical | 131 | 33 | 1.50 | 0.04 | 149 | 19 | 1.21 | 0.5 | |
|
| |||||||||
| Nuclear grade | Non-high | 868 | 129 | 1.00 | 762 | 54 | 1.00 | ||
| High | 243 | 52 | 1.04 | 0.8 | 685 | 62 | 1.02 | 0.9 | |
|
| |||||||||
| Necrosis | Absent | 550 | 68 | 1.00 | 329 | 22 | 1.00 | ||
| Present | 561 | 113 | 1.54 | 0.01 | 1118 | 94 | 1.10 | 0.7 | |
|
| |||||||||
| Number of excisions | ≤ 2 | 1072 | 167 | 1.00 | 1290 | 100 | 1.00 | ||
| ≥ 3 | 39 | 14 | 2.11 | 0.009 | 157 | 16 | 1.18 | 0.5 | |
|
| |||||||||
| Margin status | Positive/close (≤ 2mm) | 194 | 46 | 1.00 | 313 | 30 | 1.00 | ||
| Negative (> 2mm) | 917 | 135 | 0.58 | 0.001 | 1134 | 86 | 1.00 | 0.9 | |
|
| |||||||||
| Endocrine therapy | No | 932 | 161 | 1.00 | 1057 | 98 | 1.00 | ||
| Yes | 179 | 20 | 0.57 | 0.02 | 390 | 18 | 0.45 | 0.002 | |
|
| |||||||||
| Treatment period | 1978–1998 | 294 | 89 | 1.00 | 220 | 40 | 1.00 | ||
| 1999–2010 | 817 | 92 | 0.62 | 0.003 | 1227 | 76 | 1.13 | 0.6 | |
*
Numbers do not sum to 2996 due to missing data in 438 patients
DCIS, ductal carcinoma in situ; BCS, breast-conserving surgery; HR, hazard ratio