The Impact of Local and Regional Recurrence on Distant Metastasis and Survival in Patients Treated with Breast Conservation Therapy

PURPOSE: We evaluated the effect of local recurrence (LR) and regional recurrence (RR) on distant metastasis and survival in patients treated with breast conservation therapy (BCT). METHODS: We analyzed 907 patients who were treated for invasive breast cancer between 1993 and 2006. With 53 months of follow-up, 28 patients (3.1%) developed LR in the breast and 12 patients (1.3%) developed RR before distant metastasis. LR and RR were separated into four patterns to determine the prognostic relevance of recurrence site and time to recurrence: LR within 3 years (early LR), LR after 3 years (late LR), RR within 3 years (early RR), and RR after 3 years (late RR). RESULTS: Early LR (hazard ratio [HR], 4.76; p=0.003) and early RR (HR, 18.16; p<0.001) were independent predictors of distant metastasis. In terms of overall survival, early LR (HR, 5.24; p=0.002), and early RR (HR, 18.80; p<0.001) were significantly related with poor survival. Patients with late LR/RR had a similar favorable prognosis compared with patients who never experienced LR/RR. CONCLUSION: The result suggests that time to LR/RR following BCT is a significant predictor developing a distant metastasis and surviving.