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.