Atypical dose schedule.
The Studies: That’s right, there’s not a clear one. When it comes to meningioma there are nearly as many management approaches as there are treating physicians, and no one really knows which is best. Upfront adjuvant radiation or salvage, fractionated or stereotactic radiosurgery, conventional or escalated radiation dose, small or large target volumes? The list goes on, my friends. We finally get some data with recent early reporting of two prospective trials (EORTC 22042-26042 and RTOG 0539) on “intermediate risk” (IR) atypical meningioma. Both trials are multi-armed but focus their current reports on the IR groups. The EORTC IR group consisted of de novo WHO II post-gross total resection (GTR), while the RTOG IR group included de novo WHO II post-GTR (70%) as well as recurrent WHO I tumors (30%). In the EORTC trial, 60 Gy in 30 fractions was delivered to tumor bed (GTV) plus a 1 cm CTV. In the RTOG trial, 54 Gy in 30 fractions was delivered to essentially the same volume. Conveniently, both trials had a primary endpoint of 3 year progression-free survival, which was 89% in the EORTC trial and 94% in the RTOG trial. Perhaps equally important were the rates of toxicity. While there were no grade 3+ events in the RTOG trial (54 Gy), 14% of patients in EORTC (60 Gy) had grade 3+ events. But let’s not get too carried away. Management of meningioma is a long game, so we need long-term data to see if alternative salvage approaches can measure up.
Bottom Line: Adjuvant radiation (54-60 Gy) for gross totally resected WHO II meningioma has excellent rates of tumor control (>90%) at 3 years. | Rogers, J Neurosurg 2018 & Weber, Radiother Oncol 2018