IS FROZEN-SECTION ANALYSIS OF REEXCISION LUMPECTOMY MARGINS WORTHWHILE - MARGIN ANALYSIS IN BREAST REEXCISION

Background. The authors performed reexcision lumpectomy on patients wi th breast cancer with tumor at or close to the resection margin or if the margin status was unknown. Frozen section analysis (FSA) of reexci sion lumpectomy margins was performed to allow additional excision of margins or mastectomy, saving the patient another operation or an addi tional radiation boost. Methods. The authors reviewed the accuracy of FSA of margins in 107 patients undergoing reexcision lumpectomy betwee n 1987 and 1992. There were 359 frozen sections performed on 156 speci mens. Sensitivity and specificity of FSA for each frozen section margi n, specimen, and patient were evaluated, as was gross inspection of tu mor involvement at the resection margins. The accuracy of each patholo gist's use of FSA also was evaluated. Results. FSA sensitivity per fro zen section margin, specimen, and patient was 0.90, 0.89, and 0.85, re spectively. The specificity of gross inspection was 0.97, 0.96, and 0. 96 (sensitivity, 0.44), which was significantly less accurate than tha t of FSA (P = 0.0015) or permanent section (P = 0.019). There was no s ignificant discordance between FSA and permanent section. Of 19 pathol ogists doing FSA, 6 evaluated 10 or more specimens. The error rate ran ged from 4% to 10% among pathologists with 10 or more readings, wherea s 12 of 13 pathologists with fewer readings had no errors. The final p athologist had a 100% error rate, significantly worse (range, P = 0.00 85-0.02) than any experienced pathologist. Thirty-four (32%) patients underwent additional excision (24 patients) or mastectomy (10 patients ) based on the results of FSA, which saved the patients from undergoin g another operation. No one required an additional operation or a mast ectomy because of a false FSA result. Conclusion. FSA is safe and accu rate in evaluating reexcision lumpectomy margins. Gross inspection is not reliable in margin evaluation. FSA saved an additional operation 3 2% of the time. Obtaining clear margins during one procedure eliminate s the necessity of an additional radiation boost and probably will imp rove cosmesis.