Pashayan N, et al. - In this study, researchers compared risk-stratified breast screening programs with a standard age-based screening program and no screening in terms of benefit-to-harm ratio and cost-effectiveness. They created a life-table model of a hypothetical cohort of 364,500 UK women aged 50 years with follow-up to age 85 years, which indicated that adoption of a risk-stratified screening strategy may improve cost-effectiveness and the benefit-to-harm ratio of breast screening programs.

Methods

• Findings of the Independent UK Panel of Breast Cancer Screening and risk distribution based on polygenic risk profile were utilized to create the life-table model.
• The analysis was undertaken from the National Health Service perspective.
• The modeled interventions comprised: no screening, age-based screening (mammography screening every 3 years from ages 50-69 years), and risk-stratified screening (a proportion of women 50 years of age with a risk score greater than a threshold risk were offered screening every 3 years until age 69 years) considering each percentile of the risk distribution
• The investigators performed all analyses between July 2016 and September 2017.
• Main outcomes and measures included overdiagnoses, breast cancer deaths averted, quality-adjusted life-years (QALYs) gained, costs in British pounds, and net monetary benefit (NMB).
• Uncertainty around parameter estimates was assessed using probabilistic sensitivity analyses.
• They discounted future costs and benefits at 3.5% per year.

Results

• A linear increase in the incremental cost of the program was observed with lowering of the risk threshold, when compared with no screening, with no additional QALYs gained below 35th percentile risk threshold.
• The highest NMB was evident with the risk-stratified scenario with risk threshold at the 70th percentile, among the three screening scenarios, at a willingness to pay of £20,000 (USD $26,800) per QALY gained, with a 72% probability of being cost-effective.
• At the 32nd vs 70th percentile risk threshold, risk-stratified screening would cost £20,066 (USD $26,888) vs £537,985 (USD $720,900) less, would have 26.7% vs 71.4% fewer overdiagnoses, and would avert 2.9% vs 9.6% fewer breast cancer deaths, respectively, vs age-based screening.