Solitary Pulmonary Nodules: Meta-analytic Comparison of Cross-sectional Imaging Modalities for Diagnosis of Malignancy

Abstract

To perform a meta-analysis to estimate the diagnostic accuracy of dynamic contrast material-enhanced computed tomography (CT) and magnetic resonance (MR) imaging, fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography (PET), and technetium 99m ((99m)Tc) depreotide single photon emission computed tomography (SPECT) for evaluation of solitary pulmonary nodules (SPNs). Data sources were studies published in PubMed between January 1990 and December 2005. The selected investigations were comparative and noncomparative diagnostic cohort studies to examine the operating characteristics of the four imaging modalities for evaluation of SPNs, involving at least 10 enrolled participants with histologic confirmation and having sufficient data to calculate contingency tables. A random coefficient binary regression model with disease probability conditioned on test results was used to summarize test performance and construct summary receiver operating characteristic (ROC) curves. Sensitivities, specificities, predictive values, diagnostic odds ratios, and areas under the ROC curve were calculated. Forty-four studies--10 dynamic CT, six dynamic MR, 22 FDG PET, and seven (99m)Tc-depreotide SPECT--met the inclusion criteria. (One study was included in both the FDG PET and SPECT groups.) Sensitivities, specificities, positive predictive values, negative predictive values, diagnostic odds ratios, and areas under the ROC curve were, respectively, 0.93 (95% confidence interval [CI]: 0.88, 0.97), 0.76 (95% CI: 0.68, 0.97), 0.80 (95% CI: 0.74, 0.86), 0.95 (95% CI: 0.93, 0.98), 39.91 (95% CI: 1.21, 81.04), and 0.93 (95% CI: 0.81, 0.97) for dynamic CT; 0.94 (95% CI: 0.91, 0.97), 0.79 (95% CI: 0.73, 0.86), 0.86 (95% CI: 0.83, 0.89), 0.93 (95% CI: 0.90, 0.96), 60.59 (95% CI: 5.56, 115.62), and 0.94 (95% CI: 0.83, 0.98) for dynamic MR; 0.95 (95% CI: 0.93, 0.98), 0.82 (95% CI: 0.77, 0.88), 0.91 (95% CI: 0.88, 0.93), 0.90 (95% CI: 0.85, 0.94), 97.31 (95% CI: 6.26, 188.37), and 0.94 (95% CI: 0.83, 0.98) for FDG PET; and 0.95 (95% CI: 0.93, 0.97), 0.82 (95% CI: 0.78, 0.85), 0.90 (95% CI: 0.83, 0.97), 0.91 (95% CI: 0.84, 0.98), 84.50 (95% CI: 34.28, 134.73), and 0.94 (95% CI: 0.83, 0.98) for (99m)Tc-depreotide SPECT. Dynamic CT and MR, FDG PET, and (99m)Tc-depreotide SPECT are noninvasive and accurate in distinguishing malignant from benign SPNs; differences among these tests are nonsignificant.