Fine-needle aspiration biopsy in the preoperative diagnosis of solitary thyroid nodules.

Out of a total of 200 patients with solitary thyroid nodules, 41 diagnosed by fine-needle aspiration biopsy (FNAB) (group A) and 159 by clinical and/or scintiscanning data (group B), 22 were found to have malignant neoplasias, 31 adenomas, 145 simple goiters and 2 thyroiditis. The use of the FNAB technique led to a percentage increase in the operations for malignant neoplasias, while it markedly reduced the number of surgical interventions for simple goiter. Statistical calculation of the sensitivity, specificity, negative predictive value and overall diagnostic accuracy of FNAB indexes demonstrated that FNAB is a simple, reliable, useful and cost-effective procedure.