Transbronchial lung cryobiopsy and surgical lung biopsy for interstitial lung diseases: a cost-effectiveness analysis.

OBJECTIVE: Diagnosis of interstitial lung diseases (ILDs) relies on multidisciplinary discussion. However, when uncertainty persists, histopathological evaluation is required. Surgical lung biopsy (SLB) offers high diagnostic yield but carries relevant morbidity and non-negligible mortality. Although transbronchial lung cryobiopsy (TBLC) has emerged as a less invasive alternative, its economic impact on middle-income countries remains underexplored. This study sought to evaluate the cost-effectiveness of TBLC in comparison with that of SLB for the diagnosis of ILDs from the perspective of the Brazilian public health care system. METHODS: A decision tree model compared three strategies in a hypothetical cohort of 100 patients: standalone TBLC, standalone SLB, and a step-up strategy starting with TBLC and reserving SLB for inconclusive cases. Model probabilities were obtained from an umbrella review and Brazilian public health care system data. Direct medical costs were estimated by microcosting. Sensitivity analyses assessed model robustness. RESULTS: Mean costs (in Brazilian reals [BRL]) were BRL 5,623.34 for TBLC and BRL 22,855.94 for SLB (including hospitalization). The step-up strategy was the most cost-effective, yielding higher effectiveness than standalone SLB and saving approximately BRL 1.3 million per 100 patients. The step-up approach remained dominant in sensitivity analyses. CONCLUSIONS: In the Brazilian public health care system, a step-up diagnostic pathway using TBLC first and SLB only if necessary maximizes diagnostic yield while reducing costs, hospitalizations, and mortality. These findings support TBLC as the initial procedure of choice for ILD evaluation and reinforce alignment with international evidence. They may guide policy and resource allocation in Brazil and other countries with similar health care systems.