[Fine needle aspiration cytology under ultrasonographic imaging for diagnosis of thyroid tumor]

During a 66-month period, 2849 patients with thyroid gland tumor were examined by fine needle aspiration cytology (FNA) under ultrasonographic imaging at Yamada Red Cross Hospital. Of these patients, 333 received surgical therapy and histological examinations were performed. FNA yielded an accuracy of 92.4%, a specificity of 100% and a sensitivity of 88.3%. There were 16 false-negative reports which were mainly considered to be due to calcified lesions, cystic lesion, or follicular carcinoma. Among the 188 negative cases, 24 cases (12.8%) proved to be positive by repeated FNA-Preoperative FNA provides cytological information and may assist in the determination of the operative indication. This approach resulted in an increased rate of surgery of thyroid malignancies among all thyroid gland surgeries. This method need to be improved to reduce false-negative results and the combination of FNA diagnosis and other examination is necessary.