Melissa O'NEil

Background: Palliative radiotherapy (PRT) is an effective treatment for managing symptoms of advanced cancer. At least half of all radiation treatments are delivered with palliative intent, aimed at relieving symptoms, such as pain or shortness of breath. Symptomatic patients must receive PRT quickly, therefore expeditious treatment planning is essential. Standard radiation planning requires a dedicated CT scan acquired at the cancer centre, called a ‘CT simulation’, which facilitates treatment planning (i.e. tumor delineation, placement of radiation beams and dose calculation). However, the CT simulation process creates a bottleneck and often leads to delays in starting treatment. Other researchers have indicated that CT simulation can be replaced by the use of standard diagnostic CT scans for target delineation and planning, which are normally acquired through the radiology department as part of standard patient workup. The goals of this feasibility study are to assess the efficacy, acceptability and scalability of diagnostic-CT-enabled planning, compared to conventional CT simulation planning, for patients receiving PRT to bone, soft tissue and lung disease. Methods: This is a randomized, phase II study, with 33 PRT patients to be randomized in a 1:2 ratio between conventional CT simulation (Arm 1), and the diagnostic CT enabled planning workflow (Arm 2). Patients will be stratified by treatment target volume (bone and soft tissue metastasis vs. primary or metastatic intrathoracic disease targets). The primary endpoint is the amount of time the patient spends at the cancer centre. Secondary endpoints include efficacy (rate of plan deliverability and rate of plan acceptability on blinded dose distribution review), stakeholder acceptability (based on patient and clinician perception of acceptability questionnaires) and scalability. Discussion: This study will investigate the efficacy, acceptability and scalability of a “sim-free” PRT pathway compared to conventional CT simulation. The workflow may provide opportunity for resource optimization by using pre-existing diagnostic imaging and requires minimal investment due to its similarity to current PRT models. It also offers potential benefit to patients by eliminating an imaging procedure, reducing the amount of time spent at the cancer centre, and expediting time to treatment. Trial registration: Clinicaltrials.gov identifier: NCT05233904. Date of registration: February 10, 2022; current version: 1.4 on April 29, 2022.

Introduction Patients undergoing adjuvant radiotherapy to the breast often experience radiation dermatitis ranging from mild erythema to moist desquamation. In post-lumpectomy patients, the axilla and inframammary fold are at an increased risk for friction dermatitis. Dermatitis can impact patients' quality-of-life and may require treatment break/cessation. Our objectives are to assess the efficacy of 3M Cavilon Barrier Film (BF) in preventing and/or delaying the onset of grade-two dermatitis and reducing patient-reported sensation scores. Methods A total of 55 patients were randomized to receive BF on the medial or lateral breast. BF was applied twice weekly during treatment. Skin toxicity was evaluated weekly by a blinded clinical investigator using the Skin Toxicity Assessment Tool (STAT) and the modified Radiation Therapy Oncology Group Visual Assessment Score (RTOG VAS). On day one, baseline photographs were taken; seven-to-ten days post-treatment, patients returned for photographs, the STAT/RTOG VAS, and patient-opinion questions in the form of the global questionnaire. Results The paired analysis found BF did not significantly reduce dermatitis either during or post-treatment. However, the unpaired analysis found significantly reduced RTOG VAS on the lateral compartment during treatment (BF: 0.91 vs. Control: 1.21, p = 0.0408). This difference resolved post-treatment. Additionally, BF was able to reduce pruritus (p = 0.047) on the medial components and burning sensations on the lateral components (p = 0.035). There was no significant difference between the time-to-onset or proportion of patients who developed grade-two dermatitis. Conclusion In an unpaired analysis, BF significantly reduced dermatitis on the lateral compartment during treatment. Additionally, BF significantly reduced pruritus and burning sensations. A larger study using a more reliable scoring method is required to clarify the effect of BF on radiation-associated skin toxicity.