Fine needle aspiration cytology of breast fibroadenoma - A cytohistologic correlation study of 405 cases

OBJECTIVE: To evaluate the cytohistologic correlation of breast fibroadenom a (FA) in order to assess the value of cytology in the conservative managem ent of this lesion. STUDY DESIGN A retrospective analysis of all aspirates diagnosed as FA or f ibroadenomatous lesion (n = 1,549) for which a histologic follow-up study w as available (n = 362). Forty-three aspirates, including 14 nonrepresentati ve smears, from histologically proven FAs with a different cytologic report were also included in the study. RESULTS: Cytohistologic agreement was present in 287 of the 362 cytodiagnos es. Lack of correlation was observed in 75 cases. Most diagnostic errors ac cumulated in the older patient group. The sensitivity of the cytologic diag nosis of FA was 86.9% (90.8% excluding nonrepresentative cases), with a pos itive predictive value of 79.3%. In 43 cases a histologic diagnosis of FA w as given after previous erroneous (n = 29) or nonrepresentative cytodiagnos es (n = 14). The specificity of the cytologic diagnosis of FA reached 93.8% , with a negative predictive value of 96.3% (97.5% excluding nonrepresentat ive cases). Regarding malignancy, five tumors were diagnosed as FA and were malignant. No false positive diagnoses of malignancy were given, but nine aspirates were included in the category "suspicious for carcinoma." CONCLUSION: FA of the breast remains a diagnostic challenge for the cytopat hologist. A considerable amount of benign breast lesions can mimic FA on cy tology, and such diagnostic categories as "fibroadenomatous lesion" or "con sistent with FA" are associated with low diagnostic accuracy. While the cyt ologic requisites for entering a program of conservative management of FA a re established,it seems that strict diagnostic criteria should be applied e ven at the expense of diminishing sensitivity.