Análise de custo-efetividade do rastreamento com tomografia computadorizada de baixa dose para detecção precoce de câncer de pulmão sob a perspectiva do Sistema Único de Saúde

Abstract

Lung cancer is one of the most aggressive tumors, with high lethality. Early detection of lung cancer with low-dose computed tomography has been evaluated in several countries and implemented in some. However, the implementation of screening using this technology for early detection of new cases remains questioned worldwide, but in Brazil, it has not been recommended. Thus, a cost-effectiveness assessment of a screening strategy with low-dose computed tomography for early lung cancer detection in a high-risk population under the Unified Health System perspective as a funding body. First, a systematic review was performed and synthesized the different approaches available in economic evaluations. Thirty studies selected and included in the review showed overall quality, with a well-designed methodological standard, which met more than 80% of the criteria established by the Consensus Health Economic Criteria (CHEC) list form. The analysis of the comparative efficiency between two alternatives (annual and biannual) for the early diagnosis of lung cancer, considering the screening strategy with low-dose computed tomography and the clinical management, without screening, as a reference scenario, was based on a cohort hypothetical 100,000 asymptomatic individuals, and high-risk smokers. The time horizon considered the individuals' life expectancy, and the perspective was the Brazilian Unified Health System as the funder of health care. Only the direct medical costs of items related to the diagnosis and treatment process were estimated. The outcome measure was life years gained. A discount of 5% has been applied to costs and benefits. A deterministic and probabilistic sensitivity analysis has been performed. The incremental cost-effectiveness ratio of the annual screening strategy for early lung cancer detection has been estimated at BRL 97,583.52 for each life-year gained and BRL 56,642.20 per year of life gained, with screening every two years. The deterministic analysis showed that the impact of reducing the incidence of lung cancer, in both alternatives (annual and biannual) generated almost three times the estimated expenses for the incremental cost-effectiveness ratio. For the annual survey, this increase reaches BRL 176,834.47, outside the BRL 105,000.00 threshold, while biannual screening, even doubling the expenses, would remain within the cost-effectiveness threshold currently defined for the country. The other relevant parameters (screening sensitivity for cancer detection and the proportion of stage I/II diagnoses with screening) have no impact on the final results. The probabilistic analysis showed that 52% of simulations within the established threshold correspond to the annual screening, and 94.2% to the biannual. The economic model designed to evaluate the cost-effectiveness of lung cancer screening using low-dose computed tomography compared to clinical care showed favorable results from the strategy performed every two years in a high-risk population, under the SUS perspective.