Heavy smokers should get a low-dose chest CT once a year
Original: eternity4719 · source details
Original author: eternity4719 · Chinese source: · English adaptation: parveen0029. Translation and grade notes ↗
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Cost and benefit at a glance
- Check the cost Cost ↓
- The test costs 200–400 yuan per session and takes just 10 minutes. You must also factor in follow-up tests after any false alarms, plus the anxiety that comes w…
- Then the source benefit Benefit ↓
- The NLST trial in the U.S. enrolled 53,454 participants aged 55–74 with at least 30 pack-years of smoking history and who had quit smoking no more than 15 years prior. Those who un…
In plain terms
Eligible heavy smokers who get a low-dose CT once a year have a 20% lower risk of dying from lung cancer and a 6.7% lower overall risk of death compared to those who only get regular chest X-rays. The trade-offs are extra follow-up tests after any suspicious findings and the resulting worry during the waiting period.
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Cost: what it takes
The test costs 200–400 yuan per session and takes just 10 minutes. You must also factor in follow-up tests after any false alarms, plus the anxiety that comes with waiting for results.
Benefit: what the source reports
The NLST trial in the U.S. enrolled 53,454 participants aged 55–74 with at least 30 pack-years of smoking history and who had quit smoking no more than 15 years prior. Those who underwent low-dose CT had a 20.0% relative reduction in lung cancer deaths versus those who only got chest X-rays. The 95% confidence interval is 6.8–26.7. Overall mortality dropped by 6.7% relative to controls, with a 95% CI of 1.2–13.6.
Conditions, limits and disagreements
This recommendation applies only to high-risk smokers. In the same study, 24.2% of CT recipients showed suspicious findings, yet 96.4% of those cases turned out to be false positives. For non-smokers, undergoing this test offers no benefit and only adds unnecessary anxiety.
Original references
Original bibliographic titles and links are preserved; some titles are in Chinese.
National Lung Screening Trial Research Team (2011). Reduced Lung-Cancer Mortality with Low-Dose Computed Tomographic Screening. New England Journal of Medicine：「The rate of positive screening tests was 24.2% with low-dose CT and 6.9% with radiography over all three rounds. A total of 96.4% of the positive screening results in the low-dose CT group and 94.5% in the radiography group were false positive results.」https://doi.org/10.1056/NEJMoa1102873
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