In the multivariate analysis, nominally significant associations, before multiple testing corrections, were found between XRCC1T-77C (T carriers vs. CC, OR: 2.240, 95% CI: 1.015-4.941, P=0.046), eNOS G894T polymorphisms (TT vs. G carriers, OR: 2.473, 95% CI: 1.220-5.012, P=0.012), breast diameter (OR: 1.138, 95% CI: 1.001-1.293, P=0.048), boost dose-fractionation (3 Gy vs. no boost, OR: 4.902, 95% CI: 1.458-16.483, P=0.010) and ≥ grade 2 acute radiation skin toxicity in breast cancer patients.
However, the other three coding XRCC1 variants did not influence the risk of ≥grade 2 acute skin toxicity for patients with breast cancer after radiotherapy.