Abstract

We retrospectively reviewed the results of 1,850 fine needle aspiration cytology (FNAC) of thyroid nodules performed from 1990 to 1991 in the Department of Pathology, Seoul National University Hospital. Among 1,528 cases and 322 cases aspirated by clinicians and a pathologist, 465 cases(30.4%) and 13 cases(4.0%) of the aspirates were inadequate, respectively. In 227 cases, correlation of the FNAC diagnosis and histologic diagnosis was done. Excluding the inadequate cases, the sensitivity for the detection of neoplasm(malignancy together with follicular adenoma) was 86.4% and the specificity was 70.7%. The overall diagnostic accuracy was 79.0%. There were 16 false-positive cases(7.0%), and 19 false-negative cases(8.4%). The predictive value of each cytologic diagnosis was 92% in papillary carcinoma, and 100% in Hashimoto's thyroiditis. The expectancy of malignancy was 52.8% in "suspicious malignancy" and 26.7% in "atypical lesion".

• Keywords: Thyroid nodules;Fine needle aspiration cytology;Diagnostic accuracy;False-negative;False-positive;