Low-dose computed tomography for lung cancer screening in high-risk populations: A systematic review and economic evaluation
Background: Diagnosis of lung cancer frequently occurs in its later stages. Low-dose computed tomography (LDCT) could detect lung cancer early. Objectives: To estimate the clinical effectiveness and cost-effectiveness of LDCT lung cancer screening in high-risk populations. Data sources: Bibliographic sources included MEDLINE, EMBASE, Web of Science and The Cochrane Library. Methods: Clinical effectiveness - a systematic review of randomised controlled trials (RCTs) comparing LDCT screening programmes with usual care (no screening) or other imaging screening programmes [such as chest X-ray (CXR)] was conducted. Bibliographic sources included MEDLINE, EMBASE, Web of Science and The Cochrane Library. Meta-analyses, including network meta-analyses, were performed. Cost-effectiveness - an independent economic model employing discrete event simulation and using a natural history model calibrated to results from a large RCT was developed. There were 12 different population eligibility criteria and four intervention frequencies [(1) single screen, (2) triple screen, (3) annual screening and (4) biennial screening] and a no-screening control arm. Results: Clinical effectiveness - 12 RCTs were included, four of which currently contribute evidence on mortality. Meta-analysis of these demonstrated that LDCT, with ≤ 9.80 years of follow-up, was associated with a non-statistically significant decrease in lung cancer mortality (pooled relative risk 0.94, 95% confidence interval 0.74 to 1.19). The findings also showed that LDCT screening demonstrated a non-statistically significant increase in all-cause mortality. Given the considerable heterogeneity detected between studies for both outcomes, the results should be treated with caution. Network meta-analysis, including six RCTs, was performed to assess the relative clinical effectiveness of LDCT, CXR and usual care. The results showed that LDCT was ranked as the best screening strategy in terms of lung cancer mortality reduction. CXR had a 99.7% probability of being the worst intervention and usual care was ranked second. Cost-effectiveness - screening programmes are predicted to be more effective than no screening, reduce lung cancer mortality and result in more lung cancer diagnoses. Screening programmes also increase costs. Screening for lung cancer is unlikely to be cost-effective at a threshold of £20,000/quality-adjusted life-year (QALY), but may be cost-effective at a threshold of £30,000/QALY. The incremental cost-effectiveness ratio for a single screen in smokers aged 60-75 years with at least a 3% risk of lung cancer is £28,169 per QALY. Sensitivity and scenario analyses were conducted. Screening was only cost-effective at a threshold of £20,000/QALY in only a minority of analyses. Limitations: Clinical effectiveness - the largest of the included RCTs compared LDCT with CXR screening rather than no screening. Cost-effectiveness - a representative cost to the NHS of lung cancer has not been recently estimated according to key variables such as stage at diagnosis. Certain costs associated with running a screening programme have not been included. Conclusions: LDCT screening may be clinically effective in reducing lung cancer mortality, but there is considerable uncertainty. There is evidence that a single round of screening could be considered cost-effective at conventional thresholds, but there is significant uncertainty about the effect on costs and the magnitude of benefits.
Citation
@article{t.2018,
author = {Snowsill, T. and Yang, H. and Griffin, E. and Long, L. and
Varley-Campbell, J. and Coelho, H. and Robinson, S. and Hyde, C.},
title = {Low-Dose Computed Tomography for Lung Cancer Screening in
High-Risk Populations: {A} Systematic Review and Economic
Evaluation},
journal = {Health Technology Assessment},
volume = {22},
number = {69},
date = {2018-11-01},
url = {https://tristansnowsill.co.uk/low-dose-computed-tomography-for-lung-cancer.html},
doi = {10.3310/hta22690},
langid = {en},
abstract = {Background: Diagnosis of lung cancer frequently occurs in
its later stages. Low-dose computed tomography (LDCT) could detect
lung cancer early. Objectives: To estimate the clinical
effectiveness and cost-effectiveness of LDCT lung cancer screening
in high-risk populations. Data sources: Bibliographic sources
included MEDLINE, EMBASE, Web of Science and The Cochrane Library.
Methods: Clinical effectiveness - a systematic review of randomised
controlled trials (RCTs) comparing LDCT screening programmes with
usual care (no screening) or other imaging screening programmes
{[}such as chest X-ray (CXR){]} was conducted. Bibliographic sources
included MEDLINE, EMBASE, Web of Science and The Cochrane Library.
Meta-analyses, including network meta-analyses, were performed.
Cost-effectiveness - an independent economic model employing
discrete event simulation and using a natural history model
calibrated to results from a large RCT was developed. There were 12
different population eligibility criteria and four intervention
frequencies {[}(1) single screen, (2) triple screen, (3) annual
screening and (4) biennial screening{]} and a no-screening control
arm. Results: Clinical effectiveness - 12 RCTs were included, four
of which currently contribute evidence on mortality. Meta-analysis
of these demonstrated that LDCT, with ≤ 9.80 years of follow-up, was
associated with a non-statistically significant decrease in lung
cancer mortality (pooled relative risk 0.94, 95\% confidence
interval 0.74 to 1.19). The findings also showed that LDCT screening
demonstrated a non-statistically significant increase in all-cause
mortality. Given the considerable heterogeneity detected between
studies for both outcomes, the results should be treated with
caution. Network meta-analysis, including six RCTs, was performed to
assess the relative clinical effectiveness of LDCT, CXR and usual
care. The results showed that LDCT was ranked as the best screening
strategy in terms of lung cancer mortality reduction. CXR had a
99.7\% probability of being the worst intervention and usual care
was ranked second. Cost-effectiveness - screening programmes are
predicted to be more effective than no screening, reduce lung cancer
mortality and result in more lung cancer diagnoses. Screening
programmes also increase costs. Screening for lung cancer is
unlikely to be cost-effective at a threshold of
£20,000/quality-adjusted life-year (QALY), but may be cost-effective
at a threshold of £30,000/QALY. The incremental cost-effectiveness
ratio for a single screen in smokers aged 60-75 years with at least
a 3\% risk of lung cancer is £28,169 per QALY. Sensitivity and
scenario analyses were conducted. Screening was only cost-effective
at a threshold of £20,000/QALY in only a minority of analyses.
Limitations: Clinical effectiveness - the largest of the included
RCTs compared LDCT with CXR screening rather than no screening.
Cost-effectiveness - a representative cost to the NHS of lung cancer
has not been recently estimated according to key variables such as
stage at diagnosis. Certain costs associated with running a
screening programme have not been included. Conclusions: LDCT
screening may be clinically effective in reducing lung cancer
mortality, but there is considerable uncertainty. There is evidence
that a single round of screening could be considered cost-effective
at conventional thresholds, but there is significant uncertainty
about the effect on costs and the magnitude of benefits.}
}