Purpose: To evaluate the effect of an ipsilateral breast tumor recurrence (IBTR) after breast-conservation therapy (BCT) on survival.
Methods and materials: One hundred twenty-one women were randomized to BCT. Patients with an IBTR were analyzed to determine survival. Analysis was performed with Kaplan-Meier estimates, log-rank tests, and time-dependent covariate Cox models.
Results: At a median follow-up of 18.4 years, 27 patients had an IBTR. The median survival time after IBTR was 13.1 years. The 5-year survival rate was 91.8% (95% confidence interval [CI], 81.5-100%). The 10-year survival rate was 54.3% (95% CI, 35.8-82.6%). According to a Cox model with time-dependent covariates, the hazard ratio or relative risk of dying for those with an IBTR at <5.3 years after BCT relative to patients without an IBTR after BCT is 1.47 (95% CI, 1.02-2.12%; p = 0.04). The hazard ratio for those who relapse after 5.3 years is 0.59 (95% CI, 0.22-1.61%; p = 0.31). Age at randomization, original tumor size, and the presence of positive regional nodes at initial presentation were not found to be associated with decreased survival.
Conclusions: There seems to be a significant association of early IBTR after BCT with decreased survival. Local control should be maximized.