Table 1.
Tumour and patient characteristics, by DDRP mutation carrier status and previous RT exposure
| Characteristic | Mutation positive (n = 51) | Mutation negative (n = 196) | ||
| Previous RT | No previous RT | Previous RT | No previous RT | |
| Age at first BC, years | 40.3 | 42.4 | 41.4 | 42.3 |
| Age at second BC, years | 48.1 | 51.8 | 51.1 | 54.2 |
| Chemotherapy, n (percentage) | 11 (27) | 1 (10) | 28 (22) | 5 (7) |
| Tumour size, cm | 1.8 | 2.9 | 2.2 | 2.3 |
| Lymph node positive, n (percentage) | 12 (29) | 1 (10) | 41 (32) | 4 (6) |
| RT dosea, Gy | ||||
| Mean (range) | 1.49 (0.27–3.73) | 1.55 (0.24–5.61) | ||
| Median | 1.32 | 1.40 | ||
| Third quartile | 1.79 | 1.89 | ||
DDRP, DNA-damage repair pathway; BC, breast cancer; RT, radiation treatment. aRadiation dose to the site of the breast where the tumour had developed.