Introduction The magnetic resonance linear accelerator (MRL) offers improved soft tissue visualization to guide daily adaptive radiotherapy treatment. This manuscript aims to report initial experience using a 1.5 T MRL in the first 6 months of operation, including training, workflows, timings and dosimetric accuracy. Methods All staff received training in MRI safety and MRL workflows. Initial sites chosen for treatment were stereotactic and hypofractionated prostate, thoraco‐abdomino‐pelvic metastasis, prostate bed and bladder. The Adapt To Shape (ATS) workflow was chosen to be the focus of treatment as it is the most robust solution for daily adaptive radiotherapy. A workflow was created addressing patient suitability, simulation, planning, treatment and peer review. Treatment times were recorded breaking down into the various stages of treatment. Results A total of 37 patients were treated and 317 fractions delivered (of which 313 were delivered using an ATS workflow) in our initial 6 months. Average treatment times over the entire period were 50 and 38 min for stereotactic and non‐stereotactic treatments respectively. Average treatment times reduced each month. The average difference between reference planned and ionization chamber measured dose was 0.0 ± 1.4%. Conclusion The MRL was successfully established in an Australian setting. A focus on training and creating a detailed workflow from patient selection, review and treatment are paramount to establishing new treatment programmes.

The introduction of magnetic resonance (MR) linear accelerators (MR‐Linacs) into radiotherapy departments has increased in recent years owing to its unique advantages including the ability to deliver online adaptive radiotherapy. However, most radiation oncology professionals are not accustomed to working with MR technology. The integration of an MR‐Linac into routine practice requires many considerations including MR safety, MR image acquisition and optimisation, image interpretation and adaptive radiotherapy strategies. This article provides an overview of training and credentialing requirements for radiation oncology professionals to develop competency and efficiency in delivering treatment safely on an MR‐Linac.

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The introduction of magnetic resonance (MR) linear accelerators (MR‐Linac) marks the beginning of a new era in radiotherapy. MR‐Linac systems are currently being operated by teams of radiation therapists (RTs), radiation oncology medical physicists (ROMPs) and radiation oncologists (ROs) due to the diverse and complex tasks required to deliver treatment. This is resource‐intensive and logistically challenging. RT‐led service delivery at the treatment console is paramount to simplify the process and make the best use of this technology for suitable patients with commonly treated anatomical sites. This article will discuss the experiences of our department in developing and implementing an RT‐led workflow on the 1.5 T MR‐Linac.

We present the first case in the literature of a 78‐year‐old woman with recurrent cardiac sarcoma adjacent to a bioprosthetic mitral valve treated with magnetic resonance linear accelerator (MR‐Linac) guided adaptive stereotactic ablative body radiotherapy (SABR). The patient was treated using a 1.5 T Unity MR‐Linac system (Elekta AB, Stockholm, Sweden). The mean gross tumour volume (GTV) size was 17.9 cm3 (range 16.6–18.9 cm3) based on daily contours and the mean dose received by the GTV was 41.4 Gy (range 40.9–41.6 Gy) in five fractions. All fractions were completed as planned and the patient tolerated the treatment well with no acute toxicity reported. Follow‐up appointments at 2 and 5 months after the last treatment showed stable disease and good symptomatic relief. Results of transthoracic echocardiogram after radiotherapy showed that the mitral valve prosthesis was normally seated with regular functionality. This study provides evidence that MR‐Linac guided adaptive SABR is a safe and viable option for the treatment of recurrent cardiac sarcoma with mitral valve bioprosthesis.