Ultrasound-Guided Fine-Needle Aspiration Versus Fine-Needle Capillary Sampling in Evaluation of Lymph Node Metastasis of Thyroid Cancer

Background To compare the sampling adequacy and diagnostic efficiency of ultrasound-guided fine-needle aspiration with 22-, 25-gauge needles and capillary sampling with 22-gauge needle in the biopsy of cervical lymph node. Methods A total of 130 cervical lymph nodes from 103 patients were consecutively included in the prospective study. Each suspected lymph node was aspirated with a 22-gauge needle, capillary sampled with a 22-gauge needle and aspirated with a 25-gauge needle. The adequacy rates and nondiagnostic rates of obtained specimen were calculated. Results Of the 130 suspected lymph nodes, there were 77 lymph nodes<6.0 mm and 53 lymph nodes >= 6.0mm in the smallest dimension. Both FNA(22G) and FNC22G got significantly higher sampling adequacy than FNA(25G) for the total lymph nodes. For lymph nodes<6.0 mm, the sampling adequacy was significantly higher with FNA(22G) than with FNA(25G) for each parameter and the cumulative score (all P<0.05), while no difference were seen between FNA(22G) and FNC22G, and between FNC22G and FNA(25G). There were higher nondiagnostic rates for FNA(25G) compared with FNA(22G) and FNC22G in all lymph nodes and in each size subgroups. FNA(25G) yielded more diagnostically inadequate specimens than FNA(22G) and FNC22G did in the total lymph nodes (P=0.002), in lymph nodes<6.0 mm (P=0.014), and in those >= 6.0 mm (P=0.000). Conclusions FNA(22G) and FNC22G obtained more diagnostically adequate specimens than FNA(25G) in cervical lymph nodes. FNA(22G) and FNC22G may be more suitable than FNA(25G) in diagnosing cervical lymph nodes. FNA(22G) and FNC22G may yield specimens with similar quality.