Abstract
1045
Objectives: DANTE trial is a randomized study of lung cancer screening with low-dose spiral computed tomography (LDCT). In patients with suspicious lung nodules, the implementation of PET imaging and/or CT-guided core biopsy (CTB) can help improve the diagnostic accuracy and significantly reduce unnecessary and costly surgical procedures. So far however, there is no real evidence that this approach can be cost-effective. The aim of the present study was to analyze the accuracy and economic efficiency of a work-up protocol including such second-line diagnostic investigation (PET-CTB protocol), compared to pure LDCT follow-up (standard protocol) and growth assessment prior to surgical biopsy or return to standard follow-up, in patients with undetermined lung nodules.
Methods: Retrospective review of all surgical cases included in the DANTE trial and monitored in Humanitas Research Hospital Milano from 2001-2006 for lung cancer screening, was performed. Overall, 246 patients and 261 lung nodules were analyzed. The study cohort was divided into patients investigated with PET imaging, CT-guided biopsy, or both (N=98), compared to patients monitored with serial LDCT assessment and growth assessment (N=148). Diagnostic accuracy was computed by comparing the performances of the two protocols with tumor histology or long-term monitoring as reference standard. Invoices analyzed in the study comprised outpatient’s and inpatient’s costs expressed in Euro, as reimbursed by the Italian National Health System. Ineffective costs were defined as the cost of diagnostic procedures leading to potentially avoidable surgical intervention.
Results: The diagnostic accuracy of the two protocols resulted 94% (sens. 100%, spec. 94%, PPV 36%, NPV 100%) for the standard and 90% (sens. 98%, spec. 80%, PPV 85% and NPV 98%) for the PET-CTB protocol. Average costs for outpatient diagnostics resulted 694 and 1.462 euro, respectively, for the standard and PET-CTB protocol. Average inpatient’s costs for both protocols were 12.121 euro. By applying the costs to diagnostic performance (Table1), the two protocols showed comparable effectiveness in terms of total outpatient costs (94% and 90%, respectively), whereas ineffective costs consisted in 6% and 10% respectively for standard and PET-CTB protocol (p=0.361). The inpatient costs resulted effective for 36% of cases operated according to the standard protocol compared to 85% of cases with the new protocol. Ineffective costs corresponded to 64% and 15% respectively (p<0.0001).
Conclusion: In front of higher average costs for outpatients diagnostics, the implementation of PET imaging with or without CT-guided core biopsy in the diagnostic protocol of patients with suspicious lung nodules results significantly cost-effective for inpatient procedures. Research Support: Supported by the Italian Association for the Fight against Cancer (Lega Italiana per la Lotta contro i Tumori)-Milan Section, the Cariplo Foundation, and the Italian Association for the Fight against Cancer (Lega Italiana per la Lotta contro i Tumori), Rome, Italy. $$graphic_36332BCA-8CE7-4ED3-AD1F-529B9696F436$$