Diagnostic performance of 2-18FFDG PET/CT in recurrent differentiated thyroid cancer and elevated antithyroglobulin antibodies: an updated systematic review and bivariate meta-analysis

Abstract Purpose This updated systematic review and bivariate meta-analysis aimed to investigate the diagnostic performance of 2- 18 FFDG PET/CT for the detection of recurrent disease in patients with differentiated thyroid cancer (DTC) who have negative 131 I whole body scintigraphy and increased antithyroglobulin antibodies (TgAb) levels. Methods The current systematic review was carried out following a preset protocol, and the “Preferred Reporting Items for a Systematic Review and Meta-Analysis” served as a guideline for its development and reporting. A comprehensive research of the PubMed/MEDLINE, Embase and Cochrane library databases was conducted until June 2024. Results Between 2002 and 2023, 13 studies (608 patients) published on this topic were selected. The pooled sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 2- 18 FFDG PET or PET/CT were 84% (95%CI: 78−87%), 82% (95%CI: 78−86%), 72% (95%CI: 67−76%), 90% (95%CI: 87−93%) and 83% (95%CI: 79%-86%) respectively. The pooled positive and negative likelihood ratios (LR+ and LR − ) and the diagnostic odds ratio (DOR) were 0.180 (95%CI: 0.128–0.253), 3.214 (95%CI: 2.357–4.383), and 17.863 (95%CI: 10.475–30.462), respectively. No statistically significant heterogeneity among the studies was found for all the metrics evaluated (I 2 < 50%). Conclusions 2- 18 FFDG PET/CT demonstrated a good diagnostic performance in patients with DTC and increased TgAb. Although more studies are warranted, the provided evidence-based data should support the integration of 2- 18 FFDG PET/CT in clinical and diagnostic guidelines on DTC patients with increased TgAb.