Test performance of positron emission tomography and computed tomography for mediastinal staging in patients with non-small-cell lung cancer: a meta-analysis.

PURPOSE

To compare the diagnostic accuracy of computed tomography (CT) and positron emission tomography (PET) with 18-fluorodeoxyglucose (FDG) for mediastinal staging in patients with non-small-cell lung cancer and to determine whether test results are conditionally dependent (the sensitivity and specificity of FDG-PET depend on the presence or absence of enlarged mediastinal lymph nodes on CT).

DATA SOURCES

Computerized search of MEDLINE, EMBASE, BIOSIS, and CancerLit through March 2003 and reference lists of retrieved studies and review articles.

STUDY SELECTION

Studies in any language that examined FDG-PET for mediastinal staging in patients with known or suspected non-small-cell lung cancer, enrolled at least 10 participants (including at least 5 participants with mediastinal metastasis), and provided enough data to permit calculation of sensitivity and specificity for identifying lymph node involvement.

DATA EXTRACTION

One reviewer (of non-English-language studies) or 2 reviewers (of English-language studies) independently evaluated studies for inclusion, rated methodologic quality, and abstracted relevant data.

DATA SYNTHESIS

Thirty-nine studies met inclusion criteria. Methodologic quality varied, but few aspects of study quality affected diagnostic accuracy. The authors constructed summary receiver-operating characteristic curves for CT and FDG-PET. Positron emission tomography with 18-fluorodeoxyglucose was more accurate than CT for identifying lymph node involvement (P < 0.001). For CT, median sensitivity and specificity were 61% (interquartile range, 50% to 71%) and 79% (interquartile range, 66% to 89%), respectively. For FDG-PET, median sensitivity and specificity were 85% (interquartile range, 67% to 91%) and 90% (interquartile range, 82% to 96%), respectively. Fourteen studies provided information about the conditional test performance of CT and FDG-PET. Positron emission tomography with 18-fluorodeoxyglucose was more sensitive but less specific when CT showed enlarged lymph nodes (median sensitivity, 100% [interquartile range, 90% to 100%]; median specificity, 78% [interquartile range, 68% to 100%]) than when CT showed no lymph node enlargement (median sensitivity, 82% [interquartile range, 65% to 100%]; median specificity, 93% [interquartile range, 92% to 100%]; P = 0.002).

CONCLUSIONS

Positron emission tomography with 18-fluorodeoxyglucose is more accurate than CT for mediastinal staging. Positron emission tomography with 18-fluorodeoxyglucose is more sensitive but less specific when CT shows enlarged mediastinal lymph nodes.