Six of the Best, Breast 08

Abstract

Aims: Over 80 per cent of women have a preoperative diagnosis of DCIS made by core biopsy, but a cohort of patients require reoperation to complete surgical treatment. Preoperative factors which identify these women would reduce the reoperation rate. Our aim was to determine factors predictive for reoperation following breast conserving surgery for core biopsy diagnosed, screen-detected DCIS. Methods: Consecutive women diagnosed with pure DCIS (n = 160) after stereotactic core biopsy were included. A primary therapeutic local excision was attempted in all patients, with completeness of excision assessed by intraoperative specimen X-ray. Risk factors for reoperation were assessed by univariate binary logistic regression. Results: Occult invasive cancer was found at operation in 64 patients (40 per cent), with 57 women requiring reoperation for either close (<1 mm) or involved excision margins (±axillary staging, 86 per cent) or for axillary staging alone (16 per cent). Pathological and radiological estimates of DCIS size were similar (r = 0.49, P < 0.001). Conclusions: Preoperative factors and intraoperative assessment of completeness of excision did not predict for reoperation. Despite an increased preoperative core biopsy diagnosis, re-excision after primary “therapeutic” DCIS operations will remain necessary in 40 per cent of patients.