[Analysis of positive margins risk factors and long term recurrence in the conservative treatment of breast cancer].

INTRODUCTION: breast conserving therapy remains the first choice in breast cancer care for the early stages. Adequate surgical margins are essential to reduce the risk of locoregional recurrence. This study aims to identify risk factors of positive margins and locoregional recurrence.

MATERIALS AND METHODS: 437 patients who underwent a lumpectomy for invasive breast carcinoma or ductal carcinoma in situ have been included. Age, surgical margins, size, type, grade and number of tumor foci, the presence of ductal carcinoma in situ, lymph node status, expression of hormone receptors and HER-2 gene were assessed as risk factors for positive margins and locoregional recurrence.

RESULTS: The disease-free survival is 94 % at 10 years. Patients with positive margins have lower survival (92 %) than those with negative margins (96 %) (p £ 0.05). Lobular and multifocal tumors are at risk of positive margins. Tumors with positive margins, T2, grade III, triple negative and HER-2 positive neoplasms are at risk of locoregional recurrence while the expression of hormone receptors is a protective factor for local recurrence.

CONCLUSION: It appears in our study that invasive lobular and multifocal tumors may present positive surgical margins. Studies on pre- operative work-up are needed. Biological factors of the tumor seem to play a fundamental role in the locoregional recurrence or persistence of the tumor.