Patient Experience of MR-guided Radiotherapy using a 1.5T MR-Linac

Purpose or Objective
The 1.5 Tesla MR-linac device (Elekta Stockholm, Sweden) is a combination of a diagnostic 1.5 T MRI scanner and 7MV linear
accelerator and enables MR-guided radiotherapy (MRgRT) through daily adjustment of treatment plans based on the actual
MRI visualized anatomy. Adaptive treatments enable the use of smaller margins thereby including less organs at risk in the
irradiated area which potentially reduces toxicity in patients and enables safe dose escalation. However, due to daily
adaptation, treatment times are longer compared to conventional treatment and patients need to lie still in a confined
bore during treatment delivery. This study aims to evaluate patients’ on-table experience of MRgRT on a 1.5T MR-linac.
Materials and Methods
All patients treated with a daily adaptive workflow on the MR-Linac at our institution from November 2020 until April 2021,
were eligible for inclusion. Patient experience was captured after the third or fourth treatment fraction by means of an
adaptation of a validated questionnaire by McNair et al. This questionnaire includes items on physical and psychological
coping, and situational and informational needs. Answers to the statements were given on a 5 point Likert scale from
strongly disagree to strongly agree.
Results
In total 83 patients were included in this survey study. Patients were primarily male (n=73, 88%), and the median age of
participants was 70 years (range 52-90). The most frequent treatment indications were prostate cancer (n=54, 65%),
oligometastatic lymph node (n=9, 11%) and pancreas (n=8, 10%). The median number of fractions was five (range 3-17).
Responses to the statements were generally favorable (Figure 1). Ninety percent of patients (n=82) (strongly) agreed to the
statement of feeling calm during treatment on MR-Linac. Five (6%) and seven (8%) patients were uncomfortable in the
treatment position or on the table respectively. Eight patients (10%) needed more information prior to their treatment
and two (2%) patients felt they needed more information during treatment. Four (5%) patients answered (strongly) agreed
to ‘I wanted to come out of the treatment machine during my treatment’. Twenty-two (27%) patients felt tingling sensations
during their treatment.
Conclusion
Treatment on the MR-Linac is generally well tolerated. Most patients do not find treatment position uncomfortable, feel
sufficiently informed before and during their treatment and tolerate longer treatment times. One in four patients reported
tingling sensations during treatment, which warrants further investigation.