Comparison of palpation-guided fine-needle aspiration biopsy to ultrasound-guided fine-needle aspiration biopsy in the evaluation of thyroid nodules

Objective: Although fine-needle aspiration biopsy (FNAB) of thyroid nodules is a reliable and simple method, the diagnostic value may be limited by inadequate and false-negative results. In this prospective study, we compared palpation-guided FNAB (PGFNAB) with ultrasound-guided FNAB (UGFNAB) to establish the rates of inadequate material and cost-effectiveness. Design: A total of 285 thyroid nodules in 215 patients were included in the study. Palpable nodules with the greatest diameter between 1 and 2.5 cm were included in the study. PGFNAB and UGFNAB techniques were applied to the same nodule by the same operator. Cytologic evaluations were performed by the same cytologist in a blinded fashion. To provide cost analysis, the prices obtained from different hospitals were evaluated. Main outcome: The rates of inadequate material for PGFNAB and UGFNAB were significantly different as 32.3% and 21.4%, respectively (p = 0.004). There was significantly higher inadequate material rate in PGFNAB group for small-sized nodules (greatest nodule diameter between 10 and 15 mm) (p = 0.009), despite inadequate material rate was not significant for both procedures for larger sized nodules. False-negative results were 15.8% for PGFNAB and 5.6% for UGFNAB. Regarding cost analysis, the difference between the two methods was $20 on average for each patient. Conclusions: We consider UGFNAB to be superior to PGFNAB for obtaining adequate material especially for small-sized nodules, as well as providing more accurate cytologic evaluation. Indeed, the difference between the costs of two procedures might be acceptable.