A dedicated institutional clinical workflow and peer-review meeting for reirradiation.

Background and Purpose: Reirradiation (reRT) is a clinical challenge and requires organisational and technical efforts to standardise and ensure safety of practices. An institutional clinical workflow developed to manage and support systematic approach for patients' reRT was presented in this work. Materials and Methods: The workflow included a standardised approach for reRT detection and identification in patient folder in the oncology information system, previous treatment data collection, pre-treatment planning analysis of overlaps and acceptable cumulative radiobiological equieffective doses (EQD2Gy) to organs at risk, a final validation of new treatment plan using image registration and EQD2Gy dose accumulation, and a multidisciplinary peer review meeting. Statistics were compiled on reRT activity at our institution between 2020 and 2023 and the reRT peer-review meeting and the workflow were assessed through a survey addressed to young radiation oncologists (RO). Results: During the studied period, 1920 treatments were declared as reRT at our institution. The first reRT site was the brain, followed by spine, thorax and breast. The most commonly used techniques for reRT were stereotactic radiotherapy or volumetric modulated arc therapy. The youngRO survey showed that more than 80% of respondents found a benefit of peer-review meeting, with a particular interest in discussions on cumulative equieffective dose limits and cumulative doses validation. The majority of them declared they gained confidence in their reRT practice. Conclusions: The implementation of a standardized institutional workflow for reRT management helped harmonize practices within our institution to support our reRT workload. Feedback from young RO highlighted the value of peer-review meetings which contributed to increase their confidence in reRT practices.