O‐6 RESPECTIVE ROLES OF FINE NEEDLE ASPIRATION CYTOLOGY AND CORE BIOPSY IN DIAGNOSIS OF SYMPTOMATIC BREAST LESIONS

Abstract

Introduction: To evaluate and compare the respective roles of fine needle aspiration cytology and core biopsy for diagnosis of symptomatic breast lesions.Methods: Retrospective study on 589 breast fine needle aspiration cytology (FNAC) cases and 88 core biopsies (CB) with no associated FNAC, performed between January and December 2004. A computer database was searched for initial results, subsequent investigations and outcomes.Results: Of the cases that had FNAC performed as an initial investigation, the final diagnosis was reached by FNAC alone in 81.8% of cases. Of these, 59.2% were benign, 6.1% malignant and 2.4% remaining suspicious with 14.1% inadequate samples. There were 31 cases reported as suspicious (C3/C4) on FNAC, of these 14% of C3 and all of C4 were malignant on CB. Of the 86 cases that had both FNAC and CB, CB improved on the FNAC diagnosis of malignancy in 19.8% of cases, half of which were considered inadequate on FNAC. The positive predictive value of malignant cases was 100%, and the negative predictive value 98%. The absolute sensitivity of FNAC in this study was 65% and complete sensitivity 72%. The false negative rate was 8% and false positive rate 0%. The diagnosis of 88 CB without FNAC showed 37.5% to be malignant and 60.2% as benign, with 2.3% as inadequate biopsies.Discussion: FNAC remains the first line investigation in symptomatic breast lesions. Its best use is in the diagnosis of benign disease which constitutes over two thirds of patients in our practice. In suspicious and clinically malignant lesions, it is complemented by CB which may provide additional information relevant to management. In conclusion, the majority benign findings in our patients who had CB without prior FNAC, does not justify the use of CB as a first line investigation. CB is indicated in cases of inadequate or suboptimal FNAC. The continuous use of suspicious categories (C3/C4) in breast cytology is justified by the subsequent outcomes, both benign and malignant.