Definition of a positive test result in computed tomography screening for lung cancer

Claudia I. Henschke, Rowena Yip, David F. Yankelevitz, James P. Smith

Research output: Contribution to journalArticlepeer-review

189 Scopus citations

Abstract

Background: Low-dose computed tomography screening for lung cancer can reduce mortality among high-risk persons, but "false-positive" findings may result in unnecessary evaluations with attendant risks. The effect of alternative thresholds for defining a positive result on the rates of positive results and cancer diagnoses is unknown. Objective: To assess the frequency of positive results and potential delays in diagnosis in the baseline round of screening by using more restrictive thresholds. Design: Prospective cohort study. Setting: Multi-institutional International Early Lung Cancer Action Program. Patients: 21 136 participants with baseline computed tomography performed between 2006 and 2010. Measurements: The frequency of solid and part-solid pulmonary nodules and the rate of lung cancer diagnosis by using current (5 mm) and more restrictive thresholds of nodule diameter. Results: The frequency of positive results in the baseline round by using the current definition of positive result (any parenchymal, solid or part-solid, noncalcified nodule ≥5.0 mm) was 16% (3396/21136). When alternative threshold values of 6.0, 7.0, 8.0 and 9.0 mm were used, the frequencies of positive results were 10.2% (95% CI, 9.8% to 10.6%), 7.1% (CI, 6.7% to 7.4%), 5.1% (CI, 4.8% to 5.4%), and 4.0% (CI, 3.7% to 4.2%), respectively. Use of these alternative definitions would have reduced the work-up by 36%, 56%, 68%, and 75%, respectively. Concomitantly, lung cancer diagnostics would have been delayed by at most 9 months for 0%, 5.0% (CI, 1.1% to 9.0%), 5.9% (CI, 1.7 to 10.1%), and 6.7% (CI, 2.2% to 11.2%) of the cases of cancer, respectively. Limitation: This was a retrospective analysis and thus whether delays in diagnosis would have altered outcomes cannot be determined. Conclusion: These findings suggest that using a threshold of 7 or 8 mm to define positive results in the baseline round of computed tomography screening for lung cancer should be prospectively evaluated to determine whether the benefits of decreasing further work-up outweigh the consequent delay in diagnosis in some patients. Primary Funding Source: The Flight Attendant Medical Research Institute and the American Legacy Foundation.

Original languageEnglish
Pages (from-to)246-252
Number of pages7
JournalAnnals of Internal Medicine
Volume158
Issue number4
DOIs
StatePublished - 19 Feb 2013

Fingerprint

Dive into the research topics of 'Definition of a positive test result in computed tomography screening for lung cancer'. Together they form a unique fingerprint.

Cite this