How cost-effective is a biomarker and low-dose CT scan compared to standard care in the early diagnosis of Lung cancer?

Problem

Diagnostic blood tests have the potential to identify lung cancer in people at high risk, detecting lung cancer at an early stage with associated survival advantages. We conducted an economic evaluation to assess the cost-effectiveness of a screening intervention, using the EarlyCDT®-Lung Test with subsequent x-ray and low-dose chest CT scans (LDCT) for patients with a positive test result, compared to both usual care and LDCT screening for the whole target population.

Approach

A lifetime analyses with a UK NHS and personal social services perspective was conducted using a decision model for a target population of 1,000 individuals, where model parameters came from the ECLS study and literature. The model simulated the probability distribution of stage at cancer detection (early vs. late) for each evaluated alternative. Quality adjusted life years assigned to patients was dependent on stage at detection, costs dependent on the diagnostic pathway followed by patients and on cancer stage at diagnosis. We estimated net monetary benefit (NMB) at policy relevant cost-effectiveness thresholds for base-case, deterministic sensitivity, and scenario analyses.

Findings

The base case incremental NMB of the ECLS intervention compared to no screening were £2,890 (95% CI: -£92,700, £97,500) and £90,800 (95% CI: -£56,700, £237,000) respectively for a cost-effectiveness threshold of £20,000 and £30,000 per QALY. The same figures compared LDCT screening were respectively £183,000 (95% CI: £90,000, £278,000) and £103,000 (95% CI: -£39,400, £248,000). A deterministic sensitivity analysis showed that the cost-effectiveness results change with modifications of the prevalence of lung cancer in the target population and with variations in the cost of the EarlyCDT®-Lung Test. A scenario analysis confirmed that the EarlyCDT®-Lung Test performs better than a zero-cost random test and showed that if the sensitivity of the test is assumed 25% (rather than base case 52%) the ECLS intervention would further be not cost effective at a £30,000 per QALY threshold.

Consequences

The base case analysis results estimated that the ECLS intervention is the most cost-effective alternative, with highest probability, when compared to no screening or LDCT screening. This result may change with modifications of the parameters prevalence of lung cancer and EarlyCDT®-Lung Test cost, suggesting that the three alternatives considered in the main analysis could be potentially cost-effective for some specific risk of the target population and the cost of testing.