Management of cystic or predominantly cystic thyroid nodules: role of simple aspiration of internal fluid

Abstract

Purpose: The purpose of this study is to evaluate the efficacy of simple aspiration of cystic thyroid nodules by comparing with control groups to exclude the occurrence of spontaneous regression by the definition of current guidelines of American Thyroid Association. Materials and methods: 217 nodules from 210 patients with cystic thyroid nodules (cystic portion450%) were included. Nodules were classified into three groups as follows: Group 1, observation only; Group 2, fine needle aspiration (FNA) without aspiration of internal fluid; and Group 3, FNA after aspiration of internal fluid. Significant nodule size change was defined as a difference in the largest diameter of 20%, as seen on the last follow-up ultrasound (US) compared to the initial US. Results: Demographic characteristics did not show significant differences among the three groups except for the patient age (p = 0.039). Mean nodule size significantly decreased only in group 3 (p = 0.005). Significant nodule size reductions were observed in 22.0% (13/59) in group 1, 25.7% (28/109) in group 2, and 40.8% (20/49) in group 3, respectively. Conclusions: Aspiration of internal fluid should be considered as the first-line procedure for both the diagnosis and treatment of cystic or predominantly cystic thyroid nodules.