Table 1.
Demographic and disease characteristics
| Preoperative boost [n = 89] | Postoperative boost [n = 48] | Contemporary Canadian hypofractionation patients [n = 89] | |
|---|---|---|---|
| Dose fractionation | 3.33 Gy × 4 fx boost → surgery → 3.33 Gy × 11 fx WBRT | Surgery → 3.33 Gy × 11 fx WBRT → 3.33 Gy × 4 fx boost | Surgery → 2.67 Gy × 16 fx → 2.50 Gy × 4 fx boost |
| Age, years [median (range)] | 63 (40–79) | 58 (35–80) | 61 (40–84); p = 0.06 |
| Race | |||
| White | 63 (70.8) | 32 (66.7) | 30 (33.7) |
| Black | 14 (15.7) | 8 (16.7) | 5 (5.6) |
| Asian | 6 (6.7) | 6 (12.5) | 30 (33.7) |
| Other | 2 (2.2) | 1 (2.1) |
23 (25.8) p < 0.001a |
| Ethnicity | |||
| Non-Hispanic | 72 (80.9) | 42 (87.5) | 74 (83.1) |
| Hispanic | 17 (19.1) | 5 (10.4) |
15 (16.9) p = 0.70 |
| Histology | |||
| DCIS | 15 (16.9) | 12 (25.0) | 35 (39.3) |
| IDC | 59 (66.3) | 30 (62.5) | 48 (53.9) |
| ILC | 12 (13.5) | 4 (8.3) | 2 (2.2) |
| Other invasive | 3 (3.4) | 0 (0.0) |
4 (4.5) p = 0.002a |
| pT, mm [median (range)] | 10 (0–37) | 11 (1–49) |
11.5 (0–72) p = 0.12 |
| Node status | |||
| N0 | 85 (95.5) | 45 (93.8) | 87 (97.8) |
| N+ | 4 (4.5) | 2 (4.2) |
2 (2.2) p = 0.68 |
| Laterality | |||
| Right | 49 (55.0) | 28 (58.3) | 48 (53.9) |
| Left | 40 (44.9) | 17 (35.4) |
41 (46.1) p = 0.88 |
| ER status | |||
| ER+ | 82 (92.1) | 36 (75.0) | 85 (95.5) |
| ER− | 7 (7.9) | 10 (20.8) |
4 (4.5) p = 0.54 |
| PR status | |||
| PR+ | 74 (83.1) | 28 (58.3) | 79 (88.8) |
| PR− | 15 (16.9) | 18 (37.5) |
9 (10.1) p = 0.27 |
| HER2 status | |||
| HER2+ | 4 (4.5) | 8 (16.7) | 1 (1.1) |
| HER2−/NR | 85 (95.5) | 38 (79.2) |
88 (98.9) p = 0.37 |
| Grade | |||
| 1 | 21 (23.6) | 1 (2.1) | 13 (14.6) |
| 2 | 51 (57.3) | 27 (56.3) | 54 (60.7) |
| 3 | 11 (12.4) | 17 (35.4) |
20 (22.5) p = 0.11 |
Data are expressed as n (%) unless otherwise specified
Gy Gray, fx fractions, WBRT whole-breast radiation therapy, DCIS ductal carcinoma in situ, IDC invasive ductal carcinoma, ILC invasive lobular carcinoma, pT pathologic tumor size, ER estrogen receptor, PR progesterone receptor, HER2 human epidermal growth factor receptor 2, NR no record
aNo association was found with re-excision status using logistic regression