Busschaert et al 2026
JAMA network open · 2026 · Belgium · Proton
This Belgian cost-utility study, taking the national health care payer's perspective, used a state-transition microsimulation of 1,000,000 simulated Belgian women with breast cancer, reflecting national incidence and survival and stratified by baseline cardiovascular risk, smoking status and age. It compared proton therapy with photon radiotherapy delivered either by deep inspiration breath-hold (DIBH) or free breathing (FB), across left- and right-sided tumours with and without regional nodal irradiation. The study concluded that proton therapy was unlikely to be cost-effective for most Belgian patients under current cost conditions, with a small high-risk subset potentially reaching cost-effectiveness against free-breathing photons under the most optimistic cost scenario.
What it compared
Proton therapy versus photon radiotherapy (by DIBH or free breathing) in a simulated cohort of Belgian women with breast cancer, stratified by cardiovascular risk, smoking status, age, laterality and regional nodal irradiation.
What it found
Proton therapy was not cost-effective in any scenario under base-case assumptions. The highest ICER reported for the most favourable subgroup, proton versus photon free breathing in moderate-to-high baseline cardiovascular risk patients with left-sided irradiation and regional nodal irradiation, was €292 438 per QALY (95% CI €290 598-294 299), against a willingness-to-pay threshold of €45 000 per QALY. Versus photon DIBH, ICERs exceeded €700 000 per QALY across all comparisons under the most optimistic cost scenario.
What to keep in mind
The price year is given as 2024 euros, but the particle cost and comparator cost assumptions are not stated in the paper, the time horizon is not stated, and the cohort is simulated rather than observed, so the results depend heavily on modelled complication probabilities and on cost scenarios that were not fully specified.
The figures it reported
- €292 438 (95% CI €290 598-294 299) per QALYProton vs photon free breathing; moderate-to-high baseline CV risk, left-sided irradiation with regional nodal irradiation
- exceeding €700 000 per QALYProton vs photon DIBH, all subgroups (under most optimistic cost scenario)
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
- Simulated cohort of 1,000,000 Belgian women with breast cancer, reflecting national incidence and survival, stratified by baseline cardiovascular risk, smoking status and age (310,000 aged 60-69 years)
- Comparator
- Photon radiotherapy delivered via deep inspiration breath-hold (DIBH) or free breathing (FB)
- Indication
- Breast cancer (left- and right-sided; with and without regional nodal irradiation)
- Study design
- Cost-utility analysis; state-transition microsimulation model; outcome measured in QALYs (ICER per QALY gained)
- Time horizon
- not reported by this study
- Delivery technique
- not reported by this study
- Perspective
- Belgian health care payer
- Currency
- EUR (€)
- Price year
- 2024 (all cost data converted to 2024 Belgian euros)
- Willingness-to-pay threshold
- €45 000 per QALY
- Discount rate
- 3.0% for costs, 1.5% for QALYs (Belgian guidelines)
- Cost of the particle course assumed
- not reported by this study
- Cost of the comparator assumed
- not reported by this study
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 under base-case assumptions in any scenario. Cost-effective vs photon FB only under the most optimistic cost scenario (full treatment capacity and 15% reduction in proton costs), in roughly 3.6% of simulated patients, concentrated in moderate-to-high baseline cardiovascular risk patients with left-sided irradiation and regional nodal irradiation. Not cost-effective vs photon DIBH in any subgroup under that scenario.
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.