Correlation and Accuracy Between Fine Needle Aspiration Cytology of Thyroid Lesions and Histopathologic Diagnosis: Analysis of 322 Histopathologically Confirmed Cases

Koo, Jaseung; Jung, Woo Hee; Yang, Seokwoo; Hong, SoonWon

Abstract

Fine needle aspiration (FNA) cytology is the decisive test in the preoperative diagnostics of thyroid nodules. Here we share our institutional experience about thyroid aspiration and give suggestions for suspicious cytology results. Three hundred twenty-two cases in 270 patients (mean age 47.4 years, 243 women and 27 men) who underwent thyroidectomy were reviewed. Among the 322 cases, the FNA diagnosis of "positive for malignancy" was 87 cases (27.0%), "suggestive of malignancy" 30 cases (9.3%), "suspicious for malignancy" 61 cases (18.9%), "negative for malignancy" 102 cases (31.7%), and "unsatisfactory smear" 42 cases (13.0%). Eighty seven cases (100%) out of "positive for malignancy", 29 cases (96.7%) out of "suggestive of malignancy", and 39 cases (64.0%) out of "suspicious for malignancy" were papillary carcinoma (148 cases, 95.5%), or follicular carcinoma (2 cases, 1.3%), or metastatic carcinoma (1 case, 0.6%). Seventeen patients who had only negative or unsatisfactory cytology underwent thyroidectomy and nine cases (52.9%) were papillary carcinoma. We suggest that: the cytology diagnosis of "suggestive of malignancy" could be regarded as "positive for malignancy", the cytology diagnosis of "suspicious of malignancy" should be carefully correlated with clinico-radiologic manifestation, and even a negative or unsatisfactory smear should be carefully followed up.