Palpable thyroid nodules are present in 4–7% of the
adult population. The incidence of thyroid cancer in a
clinically solitary thyroid nodule or in a multinodular goiter is <5% in nonendemic areas.1–4
Thyroid nodules constitute the mean indication for fineneedle aspiration (FNA) biopsy, and the goal of this diagnostic procedure is to detect thyroid neoplasms for surgical resection and to identify non-neoplastic lesions that
may be managed conservatively.5
To rely on the FNA diagnosis when deciding for or
against thyroidectomy, surgeons need an accurate assessment of the incidence of false-positive and false-negative
biopsy results and a management strategy for those nodules considered to be indeterminate, most notably follicular lesions. In particular, the diagnosis of follicular carcinoma usually requires an assessment of vascular or capsular (thyroid capsule or tumor capsule or both) invasion,
findings that necessitate histologic evaluation. Consequently, this diagnosis can only be suspected from FNA
biopsies.6 In an attempt to resolve these important clinical
issues, we report here our experience with FNA biopsy of
the thyroid in a consecutive series of patients who underwent thyroidectomy in our Institute. We specifically
focused on the FNA results that were false-positive, falsenegative, and indeterminate for malignancy to determine
the limitations and potential pitfalls of the clinical interpretation of FNA biopsy results.
