June 30, 2005
Background: The reported accuracy of transbronchial needle aspiration (TBNA) for mediastinal staging in non- small cell lung cancer (NSCLC) varies widely. We performed a meta-analysis to estimate the accuracy of TBNA for mediastinal staging in NSCLC.
Methods: We searched Medline, Embase and the bibliographies of retrieved articles, with no language restriction, for studies evaluating TBNA accuracy. We used meta-analytic methods to construct summary receiver- operating characteristic curves and to pool sensitivity and specificity.
Results: Thirteen studies met inclusion criteria, including six studies that surgically confirmed all TBNA results and enrolled at least 10 patients with and without mediastinal metastasis (tier 1). Methodologic quality varied, but did not affect diagnostic accuracy. In tier 1 studies, the median prevalence of mediastinal metastasis was 34%. Using a random effects model, the pooled sensitivity and specificity were 39% (95% CI, 17% to 61%) and 99% (95% CI, 96% to 100%), respectively. Compared with tier 1 studies, median prevalence of mediastinal metastasis (81%; p=0.002) and pooled sensitivity (78%; 95% CI, 71% to 84%; p=0.009) were higher in non-tier 1 studies. Sensitivity analysis confirmed that the sensitivity of TBNA depends critically on the prevalence of mediastinal metastasis. The pooled major complication rate was 0.3% (95%CI, 0.01% to 4%).
Conclusions: When properly performed, TBNA is highly specific for identifying mediastinal metastasis in patients with NSCLC, but sensitivity depends critically on the study methods and patient population. In populations with a lower prevalence of mediastinal metastasis, the sensitivity of TBNA is much lower than reported in recent lung cancer guidelines.