Pediatric thyroid fine-needle aspiration cytology: a meta-analysis

Abstract Background There is conflicting evidence in the current literature regarding the use of fine-needle aspiration (FNA) biopsy in the diagnosis of a thyroid nodule in the pediatric population. There are numerous studies that look at the sensitivity and specificity of this test with varying results. A meta-analysis will provide further insight into this topic. Purpose Our objective was to investigate the diagnostic parameters of FNA biopsy in the diagnosis of a thyroid nodule in the pediatric population, specifically, to determine the sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) of the test in differentiating malignant vs benign tumors. Material and Methods We performed a literature search of Medline, Embase, and evidence based medicine (EBM) reviews for English studies that looked at FNA biopsy in thyroid nodules in the pediatric population, in which diagnostic values were present or could be calculated and where FNA results were compared to an acceptable reference standard. Two reviewers independently selected all abstracts, and from these, studies to review. Two reviewers also independently checked diagnostic values in the studies or calculated them from data available. A meta-analysis was performed, and pooled diagnostic test values were calculated using a random-effects, bivariate meta-regression model. Studies were also assessed for quality using the quality assessment for diagnostic accuracy studies tool. Results Twelve studies were included for review. The quality of the studies in general was good. The pooled estimate of sensitivity and specificity were 94% (95% confidence interval [CI], 86%-100%) and 81% (95% CI, 72%-91%), respectively. Assuming 20% of nodules are malignant, the accuracy, PPV, and NPV were 83.6%, 55.3%, and 98.2%, respectively. Conclusion This meta-analysis provides good evidence that FNA biopsy of thyroid nodules is a sensitive test in the pediatric population and may be a useful tool for excluding malignancy in young patients. Future prospective studies are needed to evaluate this further.