Make skipping radiotherapy the default for very low-risk breast cancer

LUMINA, PRIME II and IDEA show low local recurrence without radiotherapy in luminal A breast tumours in older women, yet most still receive it, so this idea makes omission the default pathway, with PAM50 genomic confirmation where needed, and tracks it as a quality metric. The evidence exists; the barrier is inertia and fee-for-service incentives, so payers would measure omission rate and five-year local recurrence. The test is a stepped-wedge implementation across cancer centres with registry follow-up. Being tested at scale, it addresses the bottlenecks Overdiagnosis and false alarms, Toxicity and quality of life are undervalued and Incentives reward me-too drugs and marginal gains.