Prognostic factors for survival after breast conserving therapy for stage I and II breast cancer. The role of local recurrence

Risk factors for local recurrence (LR) in a univariate analysis had a significant correlation with survival. Local and distant failure could not be regarded as independent events. We undertook a multivariate survival analysis to study the relation between LR and survival. In a retrospective study of 1026 patients treated with tumorectomy, axillary dissection and radiotherapy, factors associated with disease-specific survival (DSS) were analysed. Actuarial estimates for DSS are 91% at 5 years and 86% at 10 years. The multivariate analysis revealed five factors: clinical stage, number of affected axillary nodes, histological grade, degree of tubule formation and left-sided primary tumour. Controlling for these factors, LR appeared to be significantly correlated with DSS. The hazard rate of DSS was estimated to increase by a factor 8.8 (95% confidence interval 4.6-16.8) upon occurrence of a LR. Local recurrence per se, apart from the identified prognostic factors, is a risk factor for DSS. The exact mechanism by which LR has an influence on survival cannot be clarified from these data.