Table 2.
Characteristics of the cases and controls
| Arm A | Arm B | Overall | ||||
|---|---|---|---|---|---|---|
| Cases | Controls | Cases | Controls | Cases | Controls | |
| n = 166 | n = 287 | n = 153 | n = 270 | n = 319 | n = 557 | |
| Age, years, median (range) | 66 (49–80) | 66 (48–80) | 69 (49–80) | 67 (47–79) | 68 (49–80) | 66 (47–80) |
| Treatment, n (%) | ||||||
| BCS without RT | 29 (17.5) | 45 (15.7) | 25 (16.3) | 45 (16.7) | 54 (16.9) | 90 (16.2) |
| BCS with RT | 95 (57.2) | 186 (64.8) | 90 (58.8) | 171 (63.3) | 185 (58.0) | 357 (64.1) |
| Mastectomy without RT | 39 (23.5) | 52 (18.1) | 35 (22.9) | 47 (17.4) | 74 (23.2) | 99 (17.8) |
| Mastectomy with RT | 3 (1.8) | 4 (1.4) | 3 (2.0) | 7 (2.6) | 6 (1.9) | 11 (2.0) |
| Tumor stage, n (%) | ||||||
| I | 102 (61.4) | 181 (63.1) | 94 (61.4) | 165 (61.1) | 196 (61.4) | 346 (62.1) |
| II/III | 64 (38.6) | 106 (36.9) | 59 (38.6) | 105 (38.9) | 123 (38.6) | 211 (37.9) |
| Node status, n (%) | ||||||
| Positive | 66 (39.8) | 108 (37.6) | 56 (36.6) | 93 (34.4) | 122 (38.2) | 201 (36.1) |
| Negative | 100 (60.2) | 179 (62.4) | 97 (63.4) | 177 (65.6) | 197 (61.8) | 356 (63.9) |
| Grade, n (%) | ||||||
| I | 29 (18.7) | 64 (24.3) | 29 (20.9) | 65 (27.1) | 58 (19.7) | 129 (25.6) |
| II | 126 (81.3) | 199 (75.7) | 110 (79.1) | 175 (72.9) | 236 (80.3) | 374 (74.4) |
| Unknown | 11 | 24 | 14 | 30 | 25 | 54 |
| Her2 status, n (%) | ||||||
| Positive | 13 (8.1) | 16 (5.8) | 9 (6.1) | 16 (6.1) | 22 (7.2) | 32 (5.9) |
| Negative | 147 (91.9) | 262 (94.2) | 138 (93.9) | 248 (93.9) | 285 (92.8) | 510 (94.1) |
| Unknown | 6 | 9 | 6 | 6 | 12 | 15 |
Abbreviations: BCS – Breast conserving surgery, RT – Radiation therapy