Endosonography with lymph node sampling for restaging the mediastinum in lung cancer: A systematic review and pooled data analysis

Background: Mediastinal restaging after induction treatment is still a difficult and controversial issue. We aimed to investigate the diagnostic accuracy of endobronchial ultrasound-guided transbronchial needle aspiration and endoscopic ultrasound-guided fine-needle aspiration for restaging the mediastinum after induction treatment in patients with lung cancer. Methods: Embase and PubMed databases were searched from conception to March 2019. Data from relevant studies were analyzed to assess sensitivity and specificity of endobronchial ultrasound-guided transbronchial needle aspiration and endoscopic ultrasound-guided fine-needle aspiration, and to fit the hierarchical summary receiver operating characteristic curves. Results: A total of 10 studies consisting of 558 patients fulfilled the inclusion criteria. All patients were restaged by endobronchial ultrasound-guided transbronchial needle aspiration, endoscopic ultrasound-guided fine-needle aspiration, or both. Negative results were confirmed by subsequent surgical approaches. There were no complications reported during any endosonography approaches reviewed. The pooled sensitivities of endobronchial ultrasound-guided transbronchial needle aspiration and endoscopic ultrasound-guided fine-needle aspiration were 65% (95% confidence interval [CI], 52-76) and 73% (95% CI, 52-87), respectively, and specificities were 99% (95% CI, 78-100) and 99% (95% CI, 90-100), respectively. The area under the hierarchical summary receiver operating characteristic curves were 0.85 (95% CI, 0.81-0.88) for endobronchial ultrasound-guided transbronchial needle aspiration and 0.99 (95% CI, 0.98-1) for endoscopic ultrasoundguided fine-needle aspiration. Moreover, for patients who received chemotherapy alone, the pooled sensitivity of endosonography with lymph node sampling for restaging was 66% (95% CI, 56-75), and specificity was 100% (95% CI, 34-100); for patients who received chemoradiotherapy, the results seemed similar with a sensitivity of 77% (95% CI, 47-92) and specificity of 99% (95% CI, 48-100). Conclusions: Endosonography with lymph node sampling is an accurate and safe technique for mediastinal restaging of lung cancer.