Chest CT scan for lung cancer- pros and cons!

Primary diagnosis for lung cancer is computed tomography (CT). CT scan can be used to visualize nearly all parts of the body and is used to diagnose disease or injury as well as to plan medical, surgical or radiation treatment. A new meta-analysis study by Francesco Passiglia talks about uses of CT scan its accuracy in diagnosis of lung cancer. This study is published in the Journal of Clinical Oncology.

The objective of the study was to combine and analyze randomized clinical trials comparing computed tomography lung screening (CTLS) versus either no screening (NS) or chest x-ray (CXR) in subjects with cigarette smoking history, to provide a precise and reliable estimation of the benefits and harms associated with CTLS.

The researchers used data from all published randomized trials comparing CTLS versus either NS or CXR in a highly tobacco-exposed population were collected, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Subgroup analyses by comparator (NS or CXR) were performed. Pooled risk ratio (RR) and relative 95% CIs were calculated for dichotomous outcomes. The certainty of the evidence was assessed using the GRADE approach.

Researchers included nine eligible trials (88,497 patients). Pooled analysis showed that CTLS is associated with: a significant reduction of lung cancer related mortality (overall RR, 0.87; 95% CI, 0.78 to 0.98; NS RR, 0.80; 95% CI, 0.69 to 0.92); a significant increase of early-stage tumors diagnosis (overall RR, 2.84; 95% CI 1.76 to 4.58; NS RR, 3.33; 95% CI, 2.27 to 4.89; CXR RR, 1.52; 95% CI, 1.04 to 2.23); a significant decrease of late-stage tumors diagnosis (overall RR, 0.75; 95% CI, 0.68 to 0.83; NS RR, 0.67; 95% CI, 0.56 to 0.80); a significant increase of resectability rate (NS RR, 2.57; 95% CI, 1.76 to 3.74); a non significant reduction of all-cause mortality (overall RR, 0.99; 95% CI, 0.94 to 1.05); and a significant increase of over diagnosis rate (NS, 38%; 95% CI, 14 to 63). The analysis of lung cancer related mortality by sex revealed non significant differences between men and women (P = .21; I-squared = 33.6%).

The researchers concluded that "Despite there still being uncertainty about overdiagnosis estimate, this meta-analysis suggested that the CTLS benefits outweigh harms, in subjects with cigarette smoking history, ultimately supporting the systematic implementation of lung cancer screening worldwide."

For further information: Francesco Passiglia, Michela Cinquini, Luca Bertolaccini, Marzia Del Re, Francesco Facchinetti, Roberto Ferrara, "Benefits and Harms of Lung Cancer Screening by Chest Computed Tomography: A Systematic Review and Meta-Analysis" Journal of Clinical Oncology Volume 39 , Issue 23.