RESEARCH ARTICLE Thyroid Fine-Needle Aspiration Biopsy and Thyroid Cancer Diagnosis: A Nationwide Population-Based Study

Background Thyroid cancer is the most common endocrine gland malignancy and fine-needle aspiration biopsy is widely used for thyroid nodule evaluation. Repeated aspiration biopsies are need-ed due to plausible false-negative results. This study aimed to investigate the overall rela-tionship between aspiration biopsy and thyroid cancer diagnosis, and to explore factors related to shorter diagnostic time. Methods This nationwide retrospective cohort study retrieved data from the Longitudinal Health In-surance Database in Taiwan. Subjects without known thyroid malignancies and who re-ceived the first thyroid aspiration biopsy after 2004 were followed-up from 2004 to 2009 (n = 7700). Chi-square test, Kaplan-Meier survival analysis, and Cox proportional hazards model were used for data analysis. Results Of 7700 newly-aspirated patients, 276 eventually developed thyroid cancer (malignanc