ESTRO 2024 - Abstract Book

S5765

RTT - Education, training, advanced practice and role developments

ESTRO 2024

Purpose/Objective:

Radiographer-led planning in palliative radiotherapy is increasing, however literature tends to describe field-based techniques (Job, Holt & Bernard, 2019). Known to be effective for symptomatic relief, single field and midplane dose (MPD) treatments do not allow for dose optimisation for organ at risk sparing, nor dose escalation which might be appropriate in some cases. Volumetric (VMAT) approaches are often desired but not delivered due to additional time constraints (Fog et al, 2015). This work sought to establish whether a specialist therapeutic radiographer could appropriately localise and plan symptomatic bone metastases for VMAT. The objective was to allow for rapid access to highly conformal palliative radiotherapy that matches the timescales for field-based treatments.

Material/Methods:

The specialist therapeutic radiographer had completed previous training in palliative radiotherapy localisation as part of their MSc studies, leading to independent field placement.

Using the same principles, the radiographer contoured provisional “guide” structures for 5 patients in MIM Maestro (MIM Software) referred for palliative VMAT to bone metastases. The clinical oncologists would feed back any changes they made to these volumes.

The patient cohort included a mix of sclerotic and lytic disease.

For all patients, diagnostic imaging reports, clinic letters and the diagnostic images themselves were available to the radiographer to assist with appropriate localisation, prior to completion of CT planning scan. Consent and referral for treatment was completed by the clinical oncologist.

Time taken for the radiographer to complete contouring was recorded to give some illustration for how this pathway could fit in with the overall planning pathway.

Results:

Time taken varied according to the volume of disease burden, ranging from 30 mins to 1 hour for the larger volumes. Plan optimisation time ranged from 1 hour to 4 hours, creating an overall planning pathway of up to 5 hours plus additional time for plan checking, patient-specific QA and pre-treatment radiographer checks.

In 3 cases, no changes were made to the CTV by the clinical oncologists.

In a thoracic spine case, the guide volume was increased in size by 0.56% (from 235.76cc to 237.07cc) by the clinical oncologist to include a larger area of rib with possible extension (Fig. 1):