A two millimetre free margin from invasive cancer minimises residual disease in breast-conserving surgery

Stephen Thomas Ward (1) , Bruce Jones (1) , Alan Jewkes (1)

1 Good Hope Hospital, Rectory Road

AIMS In breast-conserving surgery, the width of free margin around a tumour to ensure adequate excision is controversial. The aim of this study was firstly to evaluate the frequency of residual disease in wider excision specimens in patients who undergo further surgery due to close margins of less than 5 millimetres. Secondly, the ability of demographic and tumour-related factors to predict the close margins was appraised. PATIENTS AND METHODS Three-hundred-and-three patients were included in the study. Patients undergoing wider excision were assessed for the presence of residual disease and this was tested for association with the width of the initial free margin. Various factors were studied for association with close or involved margins by univariate analysis. RESULTS Fifty-three percent of patients were eligible for re-excision based on the need for a 5 millimetre clearance. With a free margin of 2 mm or more from invasive cancer, the probability of finding residual disease was 2.3%. The probability of residual disease was higher for DCIS and did not decline with increasing free margin width. Tumour size, lobular cancer type, vascular invasion and nodal involvement, were associated with close margins. CONCLUSIONS We suggest that a free margin of 2 mm from invasive cancer is adequate to minimise residual disease, whereas the equivalent free margin for DCIS is unclear. Patients with large tumours and lobular cancer type should be counselled at the time of first surgery concerning the higher risk of further excision and mastectomy.

Mots clés: Medicine

Stephen Thomas Ward, Bruce Jones, Alan Jewkes. A two millimetre free margin from invasive cancer minimises residual disease in breast-conserving surgery. International Journal of Clinical Practice, 2010, 64 (12), pp.1675. ⟨10.1111/j.1742-1241.2010.02508.x⟩. ⟨hal-00585815⟩