Concordance between RTOG and EORTC prognostic criteria in low-grade gliomas.

ABSTRACT

Aim: European Organization for Research and Treatment of Cancer (EORTC) and the Radiation Therapy Oncology Group (RTOG) criteria are used to choose treatment in low-grade gliomas. However, no data exist on their concordance. Methods: Low-grade glioma patients treated at our institution from 1998 to 2015 and assessable for both RTOG and EORTC criteria were included to analyze their concordance. Surgery extension, postsurgical treatments, molecular characteristics (IDH mutation, MGMT methylation and 1p/19q codeletion) were recorded. Results: We included 99 patients. The concordance was low (50.5%; K = 0.127; p = 0.021) but for two subgroups EORTC high-risk patients were also RTOG high-risk patients (concordance 97.5%) and RTOG low-risk patients were also EORTC low-risk patients (concordance 90.9%). Conclusion: The concordance between RTOG and EORTC criteria is low. Thus, clinical trials adopting different risk criteria are not comparable.