Fine needle aspiration cytology of the breast: impact of experience on accuracy, using standardized cytologic criteria

Abstract

Objective: To evaluate the impact of experience on the accuracy of breast fine needle aspiration cytology (FNAC) using standardized microscopic criteria and review the possible complementarities between FNAC and core biopsy (CB).

Study design: We studied 292 breast FNAC samples and their subsequent biopsies. The cytologic samples were blindly reevaluated 4-7 years later, when we had gained more experience and refined our diagnostic criteria. The accuracy of the first reading was compared to that obtained at the second reading. Inadequate smears were included in the accuracy calculations.

Results: In the second reading, the identification of carcinomas and of benign lesions became more accurate. The improvement was statistically significant. Absolute sensitivity passed from 59.9% to 67.7%. Specificity increased from 52.0% to 56.0%. The inadequacy rate varied from 12.7% to 14.0% and complete sensitivity from 92.2% to 91.7%. The majority of inadequate smears were associated with benign lesions.

Conclusion: Significant improvements are associated with increased experience. A more detailed evaluation of nuclear atypia and the use of Papanicolaou-stained material were also important. Accurate selection of patients may improve specificity. FNAC could be used in a complementary way with CB.