A cost-effectiveness analysis of stereotactic ablative radiotherapy versus conventionally fractionated radiotherapy in the management of stage 1 non-small-cell lung cancer: Results from the TROG 09.02 CHISEL study.

Introduction: Stereotactic ablative radiotherapy (SABR) is a standard of care treatment for medically inoperable early-stage non-small-cell lung cancer (NSCLC). The CHISEL trial was a phase 3 randomised controlled trial that compared SABR to conventional radiation therapy (CRT). Using patient-level data, we compared the cost-effectiveness of SABR and CRT for early-stage NSCLC.

Methods: Data on treatment exposure, outcomes (recurrence, survival) and quality of life (QoL; EORTC QLQ-C30) were sourced from the trial. Quality-adjusted life years (QALYs) were estimated for the trial period using Australian utility weights for the EORTC QLQ-C30-derived QLU-C10D. Costs related to simulation, planning, delivery, verification and post-treatment monitoring were estimated by applying Australian Medicare Benefits Schedule fees. The costs of post-progression therapy and grade ≥3 toxicity were estimated using trial data and relevant literature sources. Cost-effectiveness was investigated as the incremental cost per QALY gained for SABR compared to CRT.

Results: Complete QoL data were available for 21 patients: 14 in the SABR arm and 7 in the CRT arm. Mean QALYs discounted at 5% per annum were similar between arms: 12.68 months for SABR and 12.12 months for CRT. The mean costs of delivering SABR and CRT were $4763 and $6817, respectively. The costs of monitoring were similar in both arms, $4856 and $4853 for SABR and CRT. The mean costs of post-progression therapy were $24,572 for SABR and $42,801 for CRT. The mean costs of grade ≥3 toxicity were $809 in the SABR arm and $132 in the CRT arm. Therefore, the total mean cost for SABR over the period of interest was lower for SABR than CRT. Given lower mean costs and numerically higher QALYs for SABR compared with CRT, an incremental cost-effectiveness ratio was not calculated.

Conclusion: Compared to CRT, SABR is a cost-effective treatment for early-stage NSCLC as the estimated upfront treatment cost and the cost of subsequent care are lower for SABR for comparable mean QALYs. Assessment of the lifetime QALYs and projections of cost estimation will provide a better indication of the long-term cost-effectiveness of SABR.