Primary endocrine therapy versus surgery plus endocrine therapy for early-stage breast cancer in older women without frailty: a cost-effectiveness and value of implementation analysis

Background Clinical guidelines recommend surgery for early-stage breast cancer in operable patients; however, primary endocrine therapy (PET) is often used in older women aged ≥ 70. This study aimed to estimate the cost-effectiveness and value of implementation of surgery plus adjuvant endocrine therapy (ET) compared with PET for older women with early breast cancer who are fit for surgery. Method A partitioned survival analysis model was developed using effectiveness data from the published literature (time horizon: lifetime). Health outcomes were measured as quality-adjusted life years (QALYs; EQ-5D-3L UK tariff). Direct costs were estimated from the perspective of NHS England (discount rate: 3.5%). Probabilistic sensitivity analysis and value of implementation analysis were conducted using a cost-effectiveness threshold of £20,000-£30,000 per QALY gained. Results Surgery + ET resulted in higher QALYs (4.57) compared to PET (3.87) and higher costs (£10,628 vs. £6,102). The incremental cost-effectiveness ratio (ICER) was £6,412.62 per QALY gained, indicating that surgery + ET is cost-effective compared to PET. The value of implementation analysis showed that imperfect implementation of surgery + ET resulted in a loss of 0.12 QALYs per patient, equating to 9,267 QALYs at the population level. Conclusion Surgery with adjuvant ET is a clinically effective and cost-effective strategy compared with PET for older women with ER + operable early-stage breast cancer. Strengthening adherence to national guidelines will improve population health outcomes and healthcare resource use. Future economic evaluations should focus on the value of management strategies for older patients unfit for surgery due to frailty or comorbidities.