Patient experience of head and neck treatment on a 1.5 T MR-Linac: is the ATS-lite adaptive solution tolerable?

Head and neck cancer (HNC) treatment on the Unity MR-Linac (MRL) (Elekta AB, Stockholm, Sweden) has been developed using the novel adapt-to-shape Lite (ATS-lite) method to create clinically acceptable adaptive treatments clinician-free. Here we investigate patient experience and acceptability of this technique.

Ten HNC patients treated to 65 Gy in 30 fractions with MRI-guided adaptive radiotherapy (MRIgART) within the PERMIT trial (NCT03727698), were included. Data collected comprised patient demographics, treatment time, and patient experience, using an established MRL questionnaire.Back-up plans were created for use on the conventional linac with CT guidance, to prevent missed fractions. The frequency of use was collected and categorised to reflect the cause.

The median total treatment time for ATS-lite method was 39 min. The percentage of treatments under 60 mins was 98.8 %.Questionnaire response rate was 85% and individual question response rate was 99%. Ninety-six percent of responses scored 2 or 3 on the Likert scale, a positive answer. The lowest scoring question was "I forced myself to manage the situation," with a mean (SD) of 2.4 (0.9).The MRL delivered 84.7 % of treatments. The back-up plan was used for 46 fractions, 7 attributed to patient tolerance (n = 2 patients).

Average treatment times for the ATS-lite HNC MRIgART are acceptable and faster than reported ATP treatment times. Patient-reported experience was extremely positive. Use of back-up plans attributable to lack of patient tolerance was low. This technique can used with the confidence that patient experience is not negatively impacted.