Table 1.
Overview of the baseline and treatment characteristics of the patient cohort. Data are presented as absolute numbers and percentages.
| Characteristics | N (%) | Characteristics | N (%) | Characteristics | N (%) |
|---|---|---|---|---|---|
| Median FU [y] | 20.4 | Clinical Tumor Stage | 356 | Resection type | 356 |
| Median Age [y] | 53.5 | cT1 | 3 (0.8%) | BCS | 178 (50.0%) |
| Age < 45 y | 70 (19.7%) | cT2 | 116 (32.6%) | Mastectomy | 178 (50.0%) |
| Age 45 y–55 y | 135 (37.9%) | cT3 | 155 (43.8%) | Neoadjuvant Systemic Therapy | 356 |
| Age > 55 y | 151 (42.4%) | cT4 | 82 (23.0%) | No Neoadjuvant Systemic Therapy | 15 (4.2%) |
| Side Primary Tumor | 356 | Clinical Nodal Stage | 341 | Agent Concomitant to RT | 122 (34.3%) |
| Right | 159 (44.7%) | cN0 | 171 (50.1%) | “Standard” Regime | 98 (27.5%) |
| Left | 176 (49.4%) | cN+ | 170 (49.9%) | AC/EC + Taxane | 11 (3.1%) |
| Unknown | 21 (5.9%) | Clinical Stage | 356 | AC/EC + CMF | 82 (23.0%) |
| Histological type | 356 | I | 1 (0.3%) | Combination of “Standard” Regime + One Agent | 5 (1.4%) |
| Ductal | 247 (69.4%) | IIA | 68 (19.1%) | “Substandard” Regime | 243 (68.3%) |
| Lobular | 66 (18.5%) | IIB | 124 (34.8%) | Mitoxantrone | 109 (30.6%) |
| Mixed ductal/lobular | 2 (0.6%) | IIIA | 80 (22.5%) | AC/EC (4–6 cylces) | 113 (31.7%) |
| Other | 13 (3.7%) | IIIB | 82 (23.0%) | AC/EC + Mitoxantrone | 4 (1.1%) |
| Unknown | 28 (7.9%) | IIIC | 1 (0.3%) | CMF (3–6 cycles) | 4 (1.1%) |
| Histological Grading | 356 | Growth pattern | 356 | CMF + Mitoxantrone | 7 (2.0%) |
| Grade 1 | 24 (6.7%) | Unifocal | 272 (76.4%) | Other (Taxane; Epirubicine + Taxane; EC + Vinorelbine; Epirubicine + Taxane + CMF) | 6 (1.7%) |
| Grade 2 | 138 (38.8%) | Multifocal | 27 (7.6%) | Additional Adjuvant Systemic Therapy | 44 (12.4%) |
| Grade 3 | 194 (54.5%) | Multicentric | 41 (11.5%) | 2–4x EC | 3 (0.8%) |
| Breast Cancer Subtype | 356 | Unknown | 16 (4.5%) | 3–6x CMF | 27 (7.6%) |
| HR+ Luminal A-like | 52 (14.6%) | Radiation Treatment Details | 356 | 2–4x Taxane | 10 (2.8%) |
| HR+ Luminal B-like | 168 (47.2%) | Mean Time Interval RT to Rx [days] | 193; SD = 80 | Other (CMF + Taxane; Epirubicine + Taxane; EC + Taxane) | 5 (1.4%) |
| HR+/HER2+ | 26 (7.3%) | Mean Tumor Bed Dose as EQD2 (3.7) | 64 Gy; Range: 48.6–75.5 Gy | Neoadjuvant + Adjuvant Systemic Therapy | |
| HR−/HER2+ | 25 (7.0%) | Regional Nodal Irradiation | 302 (84.8%) | “Standard” Regime | 113 (32.0%) |
| Triple Negative | 61 (17.1%) | Brachytherapy Boost + Hyperthermia | 108 (30.3%) | “Substandard” Regime | 229 (64.0%) |
| Unknown | 24 (6.7%) | Tumor Bed Boost | 340 (95.5%) | Endocrine Therapy | 275 (77.2%) |