The role of frozen section analysis of margins during breast conservation surgery

PURPOSE: The role of frozen section analysis during breast conservation surgery is undefined. Assessment of margins using permanent section evaluation is the standard method of ensuring complete tumor excision. If the margin is positive, however, surgical re-excision is necessary to reduce the likelihood of subsequent local recurrence. Therefore, biopsy of the surgical cavity with immediate pathological evaluation during lumpectomy was performed to evaluate the effect on local recurrence, the number of re-excisions, and cosmesis. PATIENTS AND METHODS: One hundred sixty patients underwent attempted lumpectomy with frozen section margin determination. One hundred forty patients were available for long-term follow-up (mean = 57 months, median = 46 months). All patients underwent attempted breast conservation surgery, which consisted of tumorectomy with excision of a greater than 1-cm rim of grossly normal tissue. Tumor margins were obtained by intraoperative biopsy with frozen section analysis of the lumpectomy cavity walls. RESULTS: In 21 patients (15%), frozen section analyses (FSA) revealed positive margins, resulting in immediate re-excision. In seven of these patients (5%), margins were persistently positive, and these patients therefore underwent mastectomy. Fourteen patients were successfully re-excised to a negative margin. The sensitivity and specificity of FSA were 91% and 100%, respectively. Five percent of patients definitively managed by lumpectomy with FSA of margins recurred locally. The mean cosmesis score after radiotherapy was 7.0 out of a possible 10, correlating with a good to excellent result. DISCUSSION: The accuracy of FSA, low recurrence rate, avoidance of reoperation, and good cosmesis indicate that intraoperative frozen section analysis should be adopted as a safe and effective method of margin analysis during breast conservation surgery.