Abstract
In recent years, fluorine 18 fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) has emerged as a new modality for detecting the primary site of cervical metastases from unknown primary carcinoma (UPC). The aim of this meta-analysis was to assess the diagnostic value of 18F-FDG PET/CT in detecting primary tumors in UPC patients with cervical metastases. After systematic search for eligible studies and data extraction, we determined pooled sensitivities and specificities across studies, calculated positive and negative likelihood ratios, and constructed summary receiver operating characteristic curves with area under the curve (AUC) and Q* obtained. We also analyzed the heterogeneity between studies based on subgroup-analysis and publication bias. Totally, 39 studies involving 1468 patients met the inclusion criteria. The pooled sensitivity and specificity were 0.90 (95% confidence interval [CI], 0.87-0.92) and 0.79 (95% CI, 0.75- 0.81), respectively. Likelihood ratio syntheses yielded overall PLR of 3.50 (95% CI, 3.00-4.08) and NLR of 0.20 (95% CI, 0.15-0.26). The AUC and Q* index were 0.8930 and 0.8238, respectively. The heterogeneity was only significantly observed in sensitivity. PET/CT is beneficial in the overall assessment of primary tumors in UPC patients with cervical metastases. Large, multicenter, and prospective studies with standard protocols are now needed to investigate the true value of PET/CT for detecting primary tumors of cervical metastases from UPC and the broad application of this method in clinical practice.
Keywords: 18F-FDG PET/CT, cervical metastasis, diagnostic value, meta-analysis, unknown primary carcinoma.
Graphical Abstract