Institute of Biomedical Engineering, National Taiwan University, Taipei, Taiwan.
Department of Orthopaedic Surgery, National Taiwan University Hospital, Taipei, Taiwan.
Cancer Med. 2023 Oct;12(19):20059-20069. doi: 10.1002/cam4.6576. Epub 2023 Sep 25.
Both nonoperative and operative treatments for spinal metastasis are expensive interventions. Patients' expected 3-month survival is believed to be a key factor to determine the most suitable treatment. However, to the best of our knowledge, no previous study lends support to the hypothesis. We sought to determine the cost-effectiveness of operative and nonoperative interventions, stratified by patients' predicted probability of 3-month survival.
A Markov model with four defined health states was used to estimate the quality-adjusted life years (QALYs) and costs for operative intervention with postoperative radiotherapy and radiotherapy alone (palliative low-dose external beam radiotherapy) of spine metastases. Transition probabilities for the model, including the risks of mortality and functional deterioration, were obtained from secondary and our institutional data. Willingness to pay thresholds were prespecified at $100,000 and $150,000. The analyses were censored after 5-year simulation from a health system perspective and discounted outcomes at 3% per year. Sensitivity analyses were conducted to test the robustness of the study design.
The incremental cost-effectiveness ratios were $140,907 per QALY for patients with a 3-month survival probability >50%, $3,178,510 per QALY for patients with a 3-month survival probability <50%, and $168,385 per QALY for patients with independent ambulatory and 3-month survival probability >50%.
This study emphasizes the need to choose patients carefully and estimate preoperative survival for those with spinal metastases. In addition to reaffirming previous research regarding the influence of ambulatory status on cost-effectiveness, our study goes a step further by highlighting that operative intervention with postoperative radiotherapy could be more cost-effective than radiotherapy alone for patients with a better survival outlook. Accurate survival prediction tools and larger future studies could offer more detailed insights for clinical decisions.
非手术和手术治疗脊柱转移瘤均为昂贵的干预措施。患者预期的 3 个月生存率被认为是决定最适宜治疗方法的关键因素。然而，据我们所知，尚无研究支持这一假设。我们旨在确定手术和非手术干预措施的成本效益，根据患者 3 个月生存率的预测概率进行分层。
使用具有四个定义健康状态的马尔可夫模型来估计脊柱转移瘤术后放疗和单纯放疗（姑息性低剂量外照射放疗）的手术干预的质量调整生命年（QALYs）和成本。模型的转移概率，包括死亡率和功能恶化的风险，来自二次和我们机构的数据。意愿支付阈值在 10 万美元和 15 万美元处预先设定。从卫生系统角度来看，分析在模拟 5 年后进行截尾，并按每年 3%的贴现率贴现结果。进行了敏感性分析以测试研究设计的稳健性。
对于 3 个月生存率>50%的患者，增量成本效益比为每 QALY 140907 美元；对于 3 个月生存率<50%的患者，增量成本效益比为每 QALY 3178510 美元；对于具有独立活动能力和 3 个月生存率>50%的患者，增量成本效益比为每 QALY 168385 美元。
本研究强调需要仔细选择患者并估计脊柱转移瘤患者的术前生存率。除了再次证实活动能力对成本效益的影响外，我们的研究更进一步强调，对于生存率较高的患者，术后放疗的手术干预可能比单纯放疗更具成本效益。准确的生存预测工具和未来更大规模的研究可以为临床决策提供更详细的见解。
