HealthDay News — A test used to diagnose lung cancer may not be as reliable in geographic regions where certain lung infections are more common, suggested the results of a study published in Journal of the American Medical Association.

To assess the accuracy of using fluorodeoxyglucose positron emission tomography (FDG-PET) to diagnose lung conditions in regions with locally endemic infectious lung diseases, Stephen A. Deppen, PhD, of the Vanderbilt University Medical Center in Nashville, and colleagues conducted a meta-analysis of 77 studies.

Overall, the ability of FDG-PET to correctly identify patients with lung cancer was 89%. The test’s specificity was 77% in adjusted analysis. When the researchers examined only geographic regions with a high prevalence of infectious lung disease, FDG-PET scans had a 16% lower average specificity, indicating that the lung diseases common in those regions may have sometimes been mistaken for lung cancer on the imaging tests.

“Knowledge of this reduction in specificity should limit the use of FDG-PET to diagnose lung cancer,” wrote the study authors. They suggested that only institutions with proven expertise in interpreting these scans in geographic areas where lung infections are common should use them to make a diagnosis of lung cancer.

References

  1. Deppen S et al. JAMA. 2014; doi: 10.1001/jama.2014.11488