Predictors of re-excision for positive or close margins in breast-conservation therapy for pT1 tumors.

International audienceBACKGROUND: An increasing number of patients with early-stage breast cancer is being diagnosed by way of population-wide mammographic screening in women. Because breast-conservation therapy (BCT) is the standard treatment, the aim of our study was to determine factors predisposing patients to re-excision for pT1 tumors. METHODS: A retrospective study was conducted at Besancon University Hospital in France. Patients with pathologic diagnosis of invasive breast carcinoma <20 mm in size (pT1) and undergoing BCT were selected. From these, "no-re-excision" and "re-excision" subgroups were constituted and compared in terms of patient and tumor characteristics. The intent of all surgeries was therapeutic. RESULTS: Of 206 patients who underwent BCT for pT1 tumors, 84 (41%) needed re-excision. After multivariate analysis, factors predicting re-excision were the absence of positive histologic diagnosis before surgery (P <.0001), limited superficial and deep surgical resection (P <.0001), multifocal lesion (P <.0001), and size of the in situ carcinoma (P <.0001). CONCLUSIONS: These predictive factors could be useful in reducing the rate of re-excision as well as in identifying patients with multifocal tumors and/or extensive in situ carcinoma whose disease would be better managed by mastectomy