Abstract
BACKGROUND: Several studies have investigated the diagnostic accuracy of serum lactate dehydrogenase (LDH) to pleural fluid adenosine deaminase ratio (cancer ratio, CR) for malignant pleural effusion (MPE), but the results were various. Therefore, we performed this systematic review and meta-analysis to ascertain the diagnostic accuracy of CR for MPE. METHODS: The PubMed and EMBASE databases were searched up to 7 June, 2019 to identify publications concerning diagnostic accuracy of CR for MPE. The sensitivities and specificities of CR in included studies were pooled with a bivariate model. A summary receiver operating characteristic (sROC) curve was used to estimate the global diagnostic accuracy of CR. Quality of the included studies was assessed with the revised tool for the quality assessment of diagnostic accuracy studies (QUADAS-2). RESULTS: Finally, five studies with 596 MPE patients and 863 benign pleural effusion (BPE) patients were included in this systematic review and meta-analysis. The pooled sensitivity and specificity of CR were 0.97 (95% CI: 0.92-0.99) and 0.89 (0.69-0.97), respectively. The area under sROC curve was 0.98 (95% CI: 0.97-0.99). The major design weaknesses of the included studies were patients selection and partial verification bias. CONCLUSIONS: CR has high diagnostic accuracy for MPE. Considering the design weaknesses of available studies, further studies with rigorous design are needed to further validate the findings of this meta-analysis.