We retrospectively evaluated the accuracy of fine-needle aspiration cytology (FNAC) in nonpalpable breast lesions detected by imaging techniques between 1995-1997. A total number of 308 lesions was investigated: 273 had been studied by means of either FNAC obtained under ultrasound (175 cases) or stereotactic guidance (98 cases). The overall sensitivity rate was 87.8%; specificity was 95.3%; the positive predictive value was 76.6%; the negative predictive value was 97.8%. Our results confirm that FNAC is quite effective in the approach to patients with nonpalpable breast lesions. It is particularly accurate in diagnosing malignancy, although a lower yield may be encountered in tumor types producing a desmoplastic stroma (tubular carcinoma, infiltrating lobular carcinoma) or in noncomedonic in situ ductal carcinoma. Discrepancy between a suspicious cytology and a negative histology is more frequent with benign lesions usually because of sampling mistake or technically inadequate smears. In particular, when smears are adequate, FNAC safely assists in ruling out the malignant lesions.
Copyright 2000 Wiley-Liss, Inc.