BEAT-Breast: Trial of DE-iPTV in Patients With Primary Breast Cancer With Brain Metastases Who Are Not Suitable for Stereotactic Radiotherapy.

Brain metastases from breast cancer are a common, and devastating, complication with survival times of 3 - 5 months from diagnosis. The main treatment approaches to brain metastases are surgery, stereotactic radiosurgery (SRS), and whole brain radiotherapy. However, it is known that most patients with brain metastases receive either whole-brain radiotherapy (WBRT) or no treatment, with relatively low rates of surgery and SRS. Since the commonest treatment in those who do have treatment is WBRT, the local team have developed an approach that is believed to be (possibly) more effective than WBRT. The objective is to evaluate this approach in patients who are not suitable to receive more aggressive treatment and who would otherwise receive WBRT. The local approach involves using a modern radiotherapy planning approach, combined with careful, intra-metastasis dose escalation (Dose Escalated internal PTV (DE-iPTV)) to deliver a higher dose to tumour, while delivering less dose to the brain. The combination of less dose to normal structures and more dose to the lesion will hopefully improve Health-related Quality of Life (HRQoL). The aim of this study is to demonstrate the feasibility of delivering complex radiotherapy, dose escalated internal PTV (DE-iPTV), and measuring quality of life at 8 weeks post-enrolment for patients with brain metastases from breast cancer who would otherwise receive WBRT. An exploratory blood-based biomarker sample collection and analysis will be completed. Furthermore, linked national cancer data will be used to measure the number of patients currently offered WBRT, including survival costs and hospital admissions, and thus provide a baseline to estimate the impact of this novel approach.