Initial study to coMpare the carbon footPRINT, patient experience and resources of standard and hypofractionated radiotherapy (IMPRINT)

Background:

The NHS aims to be net zero by 2040. Radiotherapy (RT) has a high environment impact due to (a) treating about 120,000 UK cancer patients/year (50% of all cancer patients), (b) using linear accelerators (linacs) to treat patients with high energy radiation and (c) high numbers of visits per patient (typically 15-30), with implications for patient transport.

Recent clinical trials show that shorter courses of RT (delivered over 3-5 visits) are as effective as standard courses (15-30 visits) for tumour control and toxicity in many patient groups. This approach, “hypofractionation” may significantly reduce the carbon footprint of RT, since patient travel forms 70% (Pilot study, PI: Chuter).

In addition, hypofractionation would: (a) reduce travel time to a RT centre increasing the likelihood of patients receiving a full course of RT especially for more deprived groups, (b) greater acceptability to patients, and (c) free up staff and equipment resources to help clear the backlog of cancer cases.

Aims and objectives:

The central aim is to provide evidence on the feasibility of a definitive evaluation of moving from standard to hypofractionated RT schedules. Specific objectives:

- To elicit the views of key decision-makers about the main barriers to implementing hypofractionation, with a focus on the role of carbon footprint of treatment. - To quantify the possible reduction in carbon footprint from increased adoption of hypofractionation over the UK.

- To identify the feasibility of assessing the impact of moving to hypofractionation for patients, in terms of travel, acceptability and other concerns identified. - To produce indicative estimates of the effect on workflows and hospital costs of hypofractionation versus standard RT Methods: There are four workpackages (WP):

WP1 – A cross-sectional interview study of key (n=24) decision-makers regarding the role of evidence about the carbon footprint of RT schedules in changing practice.

WP2- The carbon footprint at two RT centres will be assessed for 50 lung and 50 breast patients for both standard and hypofractionated treatment schedules (total 400 patients).

WP3 – The cohort of patients studied in WP2 from the Christie NHS Trust will be asked to complete questionnaires to assess (a) mode of transport to and from RT, (b) acceptability of treatment received, and (c) satisfaction with the treatment. This will include a nested qualitative sub-study (n=20) to Investigate patient’s abilities to recall details of travel and treatment received.

WP4 – A discrete event simulation (DES) model will be conceptualised to reflect the annual flow of patients through a RT clinic for standard and hypofractionated RT, to provide indicative estimates of the impact of treatment schedules on workflow and hospital costs. Timelines for delivery:

Interview key decision-makers (months 1-9); Estimating the carbon footprint at the 2 centres (months 1-18); Perform survey of patients (months 1-13) and interview a subset of patients (months 9-15); Create and run a discrete event simulation of the workflow of standard and hypofractionated RT (months 1-18); Dissemination event (month 18).

Anticipated impact and dissemination:

We expect this work will lay the groundwork for a definitive study to produce a robust evidence base that could help drive forward the implementation of hypofractionation by also engaging key stakeholders in the design of a definitive study.