Brodin et al 2021
Radiat Oncol · 2021 · United States · Proton
This cost-utility study modelled intensity-modulated proton therapy (IMPT) against conventional photon intensity-modulated radiotherapy (IMRT) for patients with oropharyngeal cancer treated with definitive radiotherapy in the United States, taking a societal perspective over a lifetime horizon. Normal tissue complication probability models estimated the risk of five toxicities (dysphagia, esophagitis, hypothyroidism, xerostomia and oral mucositis) for each patient's delivered plans, and these were converted into quality-adjusted life years (QALYs) lost and costs of complication management. The study concluded that proton therapy cost-effectiveness is conditional and varies greatly between individual patients, so that individualised decision-making is needed.
What it compared
Intensity-modulated proton therapy compared with conventional photon IMRT in modelled patients with oropharyngeal carcinoma treated with definitive radiation therapy, using each patient's previously delivered IMRT plan as the basis.
What it found
The median incremental cost-effectiveness ratio across all patients was US$361,405 per QALY, ranging from US$54,477 to US$1,508,845 per QALY between individual patients. The study reports US$234,201 per QALY for p16-positive tumours and US$516,297 per QALY for p16-negative tumours, and judged these against willingness-to-pay thresholds of US$100,000, US$250,000 and US$500,000 per QALY.
What to keep in mind
The base-case proton treatment cost of US$36,659 was not cost-effective, the price year is not stated, the discount rate is not reported, and the cohort was modelled from 31 previously treated IMRT patients (the abstract says 33), so the individual-level results should be read as illustrative rather than as a general estimate.
The figures it reported
- $361,405 per QALY (median)all patients
- $54,477 to $1,508,845 per QALYrange between individual patients
- $234,201 per QALYp16-positive tumors
- $516,297 per QALYp16-negative tumors
Figures are shown exactly as the paper gives them, in its own currency and price year. We do not convert between currencies: see the glossary for why.
- Patients modelled or enrolled
- Appendix: 31 patients previously treated with IMRT. The abstract states 33 patients. Age range not shown.
- Comparator
- IMRT (conventional photon therapy)
- Indication
- Oropharyngeal carcinoma
- Study design
- Cost-utility analysis using a Markov cohort model
- Time horizon
- Lifetime
- Delivery technique
- IMPT
- Perspective
- Societal
- Currency
- US$
- Price year
- not reported by this study
- Willingness-to-pay threshold
- US$100,000/QALY; US$250,000/QALY; US$500,000/QALY
- Discount rate
- not reported by this study
- Cost of the particle course assumed
- US$36,659
- Cost of the comparator assumed
- US$27,772
Whose costs were counted: a payer, a hospital, or society as a whole.
The year the costs are expressed in. Without it, a figure cannot be compared across time.
The condition attached to the finding
Not cost-effective in the base case (proton cost US$36,659). More likely cost-effective for patients with p16-positive tumors receiving comprehensive nodal irradiation at a WTP of US$250k/QALY. Also more likely cost-effective when the proton treatment cost falls below about US$21,659 (WTP US$100k and US$250k) or US$26,659 (WTP US$500k).
Reporting quality
92 out of 100 on the Quality of Health Economic Studies instrument, a 16-item checklist covering the objective, the perspective, the sources of each estimate, the handling of uncertainty, the horizon and discounting, how costs were measured, the model's transparency, the discussion of bias, and whether funding was disclosed. It measures how well the study was reported, not whether its conclusion is correct: a well-reported study can still reach a conclusion a later trial overturns.