Table 1.
Analyses of the main clinical characteristics of discovery and replication cohorts.
| Parameter | Discovery Cohort (n = 227) | Replication Cohort (n = 123) | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Controls (n = 90) |
Mild Cases (n = 92) |
Severe Cases (n = 45) |
p-Value (Case-Control) |
p-Value (Extreme Phenotypes) |
Controls (n = 64) |
Mild Cases (n = 49) |
Severe Cases (n = 10) | p-Value (Case-Control) |
p-Value (Extreme Phenotypes) |
|
| Age (yr.) at diagnosis, median (IQR) | 50 (45–55.75) | 50 (44–57) | 50 (45–56) | 0.93 | 0.98 | 54 (43.75–60) | 47 (40–53) | 61.5 (47.25–67) | 0.44 | 0.16 |
| Cumulative dose (mg/m2), median (IQR) | 300 (200–600) | 600 (100–600) | 600 (100–600) | 8.7 × 10−6 | 6.5 × 10−4 | 511 (121–720) | 540 (405–765) | 486 (115–600) | 0.92 | 0.01 |
| Location of Tumor in Left Breast, No (%) | 53 (58.89) | 42 (46.15) | 23 (50.00) | 0.09 | 0.33 | 34 (53.13) | 26 (53.06) | 3 (30.00) | 0.37 | 0.06 |
| Use of Radiotherapy, No (%) | 87 (9.67) | 81 (88.04) | 46 (100.00) | 0.18 | 0.21 | 58 (90.63) | 47 (95.92) | 10 (100.00) | 0.18 | 0.32 |
| Radiotherapy treatment in Left Breast, No (%) | 49 (54.44) | 41 (44.57) | 23 (51.11) | 0.73 | 0.63 | 34 (53.13) | 26 (53.06) | 3 (30.00) | 0.61 | 0.18 |
| Bilateral Breast Cancer, No (%) | 1 (1.11) | 0 (0) | 0 (0) | - | - | 3 (4.69) | 3 (6.12) | 0 (0) | - | - |
Abbreviations: IQR, Interquartile range. p-value in Case-Control analysis calculated using Student’s t-test for mild and severe cases against controls; p-value in Extreme Phenotypes analysis calculated using Student’s t-test for severe cases against controls. Significant p-values (p-val < 0.05) are highlighted in bold.