CTNI-70. RADIOTHERAPY QUALITY ASSURANCE IN THE ROAM/EORTC1308 ATYPICAL MENINGIOMA RANDOMISED CONTROLLED TRIAL: PROSPECTIVE REVIEW IMPROVES RADIOTHERAPY QUALITY AND CONSISTENCY

Abstract

Abstract OBJECTIVE ROAM/1308 is an international randomised controlled phase III trial comparing radiotherapy (60Gy in 30 fractions) to observation following complete surgical resection of atypical meningioma. We embedded prospective radiotherapy quality assurance (RTQA) within the trial with the aim of ensuring consistent radiotherapy planning and delivery. METHODS The radiotherapy protocol described the consensus contouring/planning guidelines. Pre-trial assessment included benchmark cases (outlining/planning) and a technology ‘Dummy Run’. Individual case reviews were undertaken. Non-conformities were classed as ‘major’ (undertreatment of dural margins/over treatment of brain or organs at risk) or ‘minor’ (for education). Resubmissions were mandated for all major non-conformities. All plans were approved before radiotherapy delivery. RESULTS The UK RTQA group coordinated European sites. The Australian RTQA group (TROG) reviewed their sites and provided all data to the UK for review. Four radiation oncologists reviewed contours and physicists/dosimetrists reviewed plans. All sites (20 UK, 25 EORTC, 11 TROG) undertook the benchmark/’Dummy Run’ cases prior to opening. Resubmissions were: UK (1 contour, 0 plans), EORTC (2 contours, 6 plans) and TROG (1 contour, 3 plans). Trial communications and outlining workshops were used to provide feedback. Radiotherapy was delivered to 30, 26 and 7 patients at 11 UK, 12 EORTC and 5 TROG sites, respectively. Overall, 25 (40%) patient cases needed resubmitting: 23 (37%) sets of outlines (2 cases twice) and 9 (14%) treatment plans (1 plan twice). CONCLUSIONS Prospective quality assurance and case review are essential to ensure consistent high-quality radiotherapy and benchmark/’Dummy Run’ alone is not sufficient. RTQA should be used for future trials in rare tumours where centres may only treat a few patients. The consistent high-quality radiotherapy in ROAM/EORTC1308 ensures the primary outcome (progression free survival: to report 2026) will be a robust assessment and any difference between treatment arms cannot be attributed to variation in radiotherapy planning or delivery.