SIGNIFICANCE OF NONDIAGNOSTIC FINE-NEEDLE ASPIRATION OF THE THYROID

Background. Fine-needle aspiration biopsy (FNAB) has been shown to be rapid and cost effective in the evaluation of thyroid nodules. The sig nificance of nondiagnostic (unsatisfactory) FNAB is uncertain, however . Methods. We reviewed 345 consecutive thyroid FNABs and identified 59 patients with initially unsatisfactory specimens. These patients had follow-up to determine whether their thyroid nodules proved to be mali gnant. Results. Three patients (5.1%) were found to have organ-confine d papillary carcinoma of the thyroid, the largest tumor mass measuring 1.2 cm. Six patients (10.2%) had benign adenomas Conclusions. In most cases of initially nondiagnostic FNAB of a thyroid nodule, neoplasia is not found subsequently. A minority of cases may still harbor malign ancy. None of our patients in whom repeated FNA was either nondiagnost ic or suggestive of benign disease were ultimately found to have a mal ignancy.