Table 1.
Clinical Characteristics of the BCCA Cohort Used in Cox Regression Modeling to Create the Modified IBTR! Version 2.0 Nomogram and the MGH Cohort Used for Validation Testing
| Characteristic | BCCA |
MGH |
||
|---|---|---|---|---|
| No. | % | No. | % | |
| No. of patients | 7811 | 664 | ||
| Median follow-up time, years | 9.4 | 9.3 | ||
| Range | 0.1-17 | 0.3-17.2 | ||
| Median age, years | 58 | 58 | ||
| Range | 17-88 | 28-89 | ||
| ≤ 40 | 670 | 8.6 | 50 | 7.5 |
| 41-45 | 804 | 10.3 | 44 | 6.6 |
| 46-50 | 1,050 | 13.4 | 96 | 14.5 |
| 51-55 | 985 | 12.6 | 94 | 14.2 |
| 56-60 | 919 | 11.8 | 90 | 13.6 |
| 61-65 | 933 | 11.9 | 65 | 9.8 |
| 66-70 | 1,012 | 13.0 | 94 | 14.2 |
| > 70 | 1,438 | 18.4 | 131 | 19.7 |
| Margin | ||||
| Positive | 788 | 10.1 | 52 | 7.8 |
| Close (< 2 mm) | 15 | 0.2 | 71 | 10.7 |
| Negative (> 2 mm) | 6,730 | 86.2 | 541 | 81.5 |
| Unknown | 278 | 3.6 | 0 | 0 |
| Lymphovascular invasion | ||||
| Present | 2,025 | 25.9 | 118 | 17.8 |
| Absent | 5,516 | 70.6 | 546 | 82.2 |
| Unknown | 270 | 3.5 | 0 | 0 |
| Tumor size, cm | ||||
| ≤ 1 | 2,096 | 25.9 | 263 | 39.6 |
| 1.1-2 | 3,675 | 47.0 | 280 | 42.1 |
| > 2 | 2,040 | 26.1 | 121 | 18.2 |
| Grade | ||||
| I | 1,359 | 17.4 | 152 | 22.9 |
| II | 3,593 | 46.0 | 331 | 49.8 |
| III | 2,544 | 32.6 | 181 | 27.3 |
| Unknown | 315 | 4.0 | 0 | 0 |
| Hormone therapy | ||||
| Yes | 3,080 | 39.4 | 404 | 60.8 |
| No | 4,731 | 60.6 | 260 | 39.2 |
| Chemotherapy | ||||
| Yes | 2,275 | 29.1 | 219 | 33.0 |
| No | 5,536 | 70.9 | 445 | 67.0 |
Abbreviations: BCCA, British Columbia Cancer Agency; MGH, Massachusetts General Hospital.