Intraoperative frozen section analysis for breast-conserving therapy in 1016 patients with breast cancer.

OBJECTIVE We evaluate the number of surgical two-stage procedures after FSA during breast-conserving therapy (clinical false negative result of FSA) and investigate the influence of microcalcifications, small tumour diameter, neoadjuvant therapy and preoperative biopsy on the clinical false negative rate of FSA. SUBJECTS We retrospectively examined 1016 patients after intraoperative FSA during breast-conserving therapy for breast cancer operated between 1995 and 2001 at the Medical University Vienna. RESULTS Only 9% of all patients had to undergo a two-stage operation due to a false negative intraoperative FSA result. The annual local recurrence rate was 1.2% in all patients with no difference between one- and two-stage operated patients. In situ and pT1 lesions were similarly distributed between one-stage and two-stage operated patients. The use of neoadjuvant therapy and stereotactic biopsy (reflecting non-palpable lesions and microcalcifications) were significantly predictive for a false negative FSA result. The use of a preoperative core biopsy, however, reduced the necessity of performing a two-stage operation. CONCLUSION Our study demonstrates that FSA leads to a low rate of two-stage operations. Small lesions and microcalcifications as well as the occurrence of intraductal cancer cells and neoadjuvant therapy increased while preoperative core biopsy reduced the false negative rate of FSA. Overall local recurrence rates after FSA were acceptable.