FDG-PET/CT in indeterminate thyroid nodules: cost-utility analysis alongside a randomised controlled trial

Abstract

Purpose To evaluate cost-effectiveness of an [18F]FDG-PET/CT-driven diagnostic workup as compared to diagnostic surgery, for thyroid nodules with Bethesda III/IV cytology. [18F]FDG-PET/CT avoids 40% of futile diagnostic surgeries for benign Bethesda III/IV nodules. Methods Lifelong societal costs and quality-adjusted life years (QALYs) were assessed for 132 patients participating in a randomised controlled multicentre trial comparing [18F]FDG-PET/CT to diagnostic surgery. The observed 1-year trial results were extrapolated using a Markov model. The probability of cost-effectiveness was estimated using cost-effectiveness acceptability curves, taking uncertainty about sampling, imputation, and parameters into account. Results The observed 1-year cost difference of [18F]FDG-PET/CT as compared to diagnostic surgery was − €1000 (95% CI: − €2100 to €0) for thyroid nodule–related care (p = 0.06). From the broader societal perspective, the 1-year difference in total societal costs was − €4500 (− €9200 to €150) (p = 0.06). Over the modelled lifelong period, the cost difference was − €9900 (− €23,100 to €3200) (p = 0.14). The difference in QALYs was 0.019 (− 0.045 to 0.083) at 1 year (p = 0.57) and 0.402 (− 0.581 to 1.385) over the lifelong period (p = 0.42). For a willingness to pay of €50,000 per QALY, an [18F]FDG-PET/CT-driven work-up was the cost-effective strategy with 84% certainty. Conclusion Following the observed reduction in diagnostic surgery, an [18F]FDG-PET/CT-driven diagnostic workup reduced the 1-year thyroid nodule–related and societal costs while sustaining quality of life. It is very likely cost-effective as compared to diagnostic surgery for Bethesda III/IV nodules. Trial registration number: This trial is registered with ClinicalTrials.gov: NCT02208544 (5 August 2014), https://clinicaltrials.gov/ct2/show/NCT02208544.

Health-related quality of life following FDG-PET/CT for cytological indeterminate thyroid nodules

“…Our previous intention-to-treat analysis of the EQ-5D-5L results demonstrated non-inferiority of an FDG-PET/CT-driven workup with regard to general HRQoL based on QALYs ( 6 , 8 ). For the current comprehensive HRQoL study, a per-protocol analysis with exclusion of crossovers was considered most appropriate, despite its known drawbacks with regard to bias ( 40 ).…”

“…Our recent randomised controlled multicentre trial confirmed that a negative FDG-PET/CT scan accurately rules out malignancy with a 94% sensitivity, avoiding 40% of futile diagnostic surgeries for benign nodules ( 6 , 7 ). Moreover, FDG-PET/CT proved cost-effective in a Dutch setting, with lower societal lifelong costs while maintaining the long-term health-related quality of life (HRQoL) in patients undergoing FDG-PET/CT-driven management as compared to routine diagnostic surgery or molecular testing ( 8 , 9 ).…”

“…Patients with a suspicious as compared to a benign molecular test result initially showed poorer HRQoL, which improved after diagnostic surgery ( 23 , 24 ). Our cost-utility study reported that the general 1-year and lifelong HRQoL, assessed using the EuroQol 5-dimension 5-level (EQ-5D-5L) questionnaire, was similar in patients undergoing FDG-PET/CT-driven management or diagnostic surgery and that cost-effectiveness was most sensitive to changes in HRQoL following hemithyroidectomy for a histopathologically benign nodule ( 8 ). Therefore, we hypothesised that temporary and/or domain-specific HRQoL differences may exist between patients undergoing active surveillance following a negative FDG-PET/CT scan and patients undergoing diagnostic surgery, specifically for a benign nodule.…”

Molecular Diagnostics and [18F]FDG-PET/CT in Indeterminate Thyroid Nodules: Complementing Techniques or Waste of Valuable Resources?

“…Although the consequential additional health care expenses had no impact on cost-effectiveness of [ 18 F]FDG-PET/CT, incidental findings can be limited by performing partial-body imaging only. 18 , 21 …”

“… 18–20 With a 94% sensitivity, [ 18 F]FDG-PET/CT accurately excludes malignancy in ITN and cost-effectively avoids 40% of futile diagnostic surgeries for benign nodules. 18 , 21 The specificity of [ 18 F]FDG-PET/CT is only 40% as many noncancerous ITN also show increased uptake of [ 18 F]FDG. 18 …”