BackgroundMultifocal breast cancers (MFBCs) present a challenge to surgeons. Although its feasibility is still controversial, breast-conserving surgery (BCS) is not contraindicated for MFBCs. The investigators retrospectively evaluated the feasibility of BCS and reviewed histopathologic findings in patients with MFBC. MethodsA total of 222 patients with MFBC who were treated with either BCS (119 patients) or mastectomy (103 patients) at a single institution between January 2002 and December 2011 were retrospectively evaluated. ResultsThe median follow-up time was 55 months (range, 10 to 102 months). Lymphovascular invasion and lymph node involvement were significantly less frequent in the BCS group (48.8% vs 62.2% for lymphovascular invasion, P = .04; 52.1% vs 71.8% for lymph node involvement, P = .002). There were no differences in local recurrence rates between the 2 groups. The overall survival rates were 92% in the BCS group and 72% in the mastectomy group (P = .000). ConclusionsBCS is a feasible and safe procedure for the removal of multifocal tumors. Extended lymphovascular invasion is associated with mortality in patients who undergo mastectomy.