Local and distant failures after limited surgery with positive margins and radiotherapy for node-negative breast cancer.

PURPOSE: To determine the outcome of patients with positive margins after lumpectomy for breast cancer and to address the issue of the relationship between local recurrences and distant metastasis in the absence of chemotherapy. METHODS AND MATERIALS: Among 3697 patients with primary breast cancer, we retrospectively analyzed 152 patients who had undergone conservative surgery with axillary dissection, had infiltrating carcinomas with positive margins, were node-negative, and received radiotherapy without chemotherapy. One-third received hormonal therapy. Endpoints were local failure and distant metastasis. Median follow-up was 72 months.
RESULTS: Five- and 10-year recurrence-free survival were 0.80 and 0.71 respectively for local recurrences, and 0.85 and 0.73 respectively for metastasis. Infiltrating carcinoma on the margins was associated with early local relapse as opposed to intraductal carcinoma. Local and distant recurrences had similar patterns of yearly-event probabilities. Hazard of relapsing from metastasis was 2.5 times higher after a local recurrence. In the multivariate analysis, negative estrogen receptors (ER-)(p = 0.0012), histologic multifocality (p = 0.0028), and no hormonal therapy (p = 0.017) predicted local relapses, while ER- (p = 0.004) and pathologic grade (p = 0.009) predicted metastasis. Hormonal therapy did not prevent early local recurrences.
CONCLUSION: In this population, reexcision is advisable for local purposes and because the data support the hypothesis that local and distant recurrences are tightly connected.