Abstract

Fine needle aspiration cytology (FNAC) has emerged as a pivotal diagnostic tool for evaluating thyroid nodules due to its minimally invasive nature and diagnostic accuracy. This study aimed to provide evidence-based recommendations for the clinical use of FNAC in the diagnosis of thyroid diseases and to identify areas for future research in this field. This study employed a systematic review and meta-analysis, adhering to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and registered with PROSPERO. A refined search strategy, combining mesh terms and text words, was approved by the PubMed help desk, covering diverse databases without restrictions. Eligibility criteria included observational studies on FNAC effectiveness in thyroid disease diagnosis. Two-phase screening and data extraction were conducted independently by author pairs. Data synthesis employed fixed or random-effects models based on heterogeneity, with sensitivity analysis, subgroup analysis, and met-regression. Initially, 1,023 distinct studies after removing duplicates were identified. Only 22 studies out of 629 were considered for inclusion and made it into the final meta-analysis and comprehensive review. All studies included in the bivariate model had a sensitivity of 85.6% (95% CI, 79.9-89.5), specificity of 71.4% (95% CI, 61.1-79.8), positive likelihood ratio of 3.0 (95% CI, 2.3-4.1), and negative likelihood ratio of 0.2 (95% CI, 0.2-0.3). FNAC stands out as a valuable and versatile diagnostic tool for thyroid nodule assessment. Its minimally invasive nature, cost-effectiveness, rapid results, and high diagnostic accuracy make it a preferred choice in clinical practice. Future research should further explore advancements in FNAC techniques and their impact on improving diagnostic outcomes in thyroid pathology.

Key words: Fine-needle aspiration cytology, thyroid disease, diagnosis, systematic review, meta-analysis