KEY POINTS
- ROAM/EORTC-1308 was an international phase III randomized trial enrolling 157 patients with newly diagnosed atypical meningioma after surgeon-assessed complete resection. Patients were assigned to adjuvant RT (n=78) or observation (n=79).
- Adjuvant treatment consisted of conventionally fractionated RT, while the control group underwent surveillance. Median follow-up was 64 months.
- Meningioma recurrence occurred in 11/78 patients (14%) with RT versus 24/79 (30%) with observation.
- Five-year disease-free survival was 79.9% with RT versus 64.3% with observation, an absolute difference of 15.6 percentage points. Adjuvant RT reduced the hazard of recurrence or death by approximately half: HR 0.51, 95% CI 0.27–0.97; p=0.0396.
- The benefit persisted after accounting for molecular risk. Adjusting for methylation class produced an HR of 0.49, while adjustment for integrated molecular score produced an HR of 0.46.
- No overall-survival difference was demonstrated. Second-line treatment for recurrence was required in 10% of patients assigned RT versus 20% assigned observation.
- No clear differences in HRQoL or formal neurocognitive testing were detected, but long-term completeness was limited: only 38% contributed HRQoL data at five years, and neurocognitive assessments also had substantial missing data.
- Radiation-related serious adverse events were uncommon. There were no treatment-related deaths, and current follow-up identified no radiation-induced cancers. Very late toxicity will require longer observation.
CLINICAL TAKEAWAY
ROAM/EORTC-1308 provides the first randomized evidence that adjuvant fractionated RT substantially reduces recurrence after complete resection of WHO grade 2 atypical meningioma. The result strongly shifts the discussion toward routinely considering postoperative RT, while individual decisions still need to balance recurrence risk against treatment volume, comorbidity and very-late toxicity; importantly, around 70% of observed patients had not recurred after approximately five years.