We re-analysed a national database of 120 patients with IDH-wild type grade II astrocytoma. EGFR amplification and pTERT mutation were analysed by FISH and gene sequencing, respectively. Kaplan-Meier curves were used for overall survival (OS).

EGFR and pTERT statuses were available in 63 and 59 cases, respectively: EGFR amplification was found in 54 (86.0%) and pTERT mutation in 29 (49.2%). EGFR-amplificated patients had a shorter OS (23.5 vs 28.4 months, P=0.01). Similarly, pTERT-mutant patients had a shorter OS (31.9 vs 192.0 months, P = 0.006). Among patients without EGFR amplification, gross total resection (GTR) correlated to longer OS as compared to partial/subtotal (PR/SBT) resection (117.9 vs 20 months, P=0.04), whereas no significant difference was seen in the EGFR-amplificated group (11.8 vs 4.5 months, P=0.4). Similarly, among patients without pTERT mutation, GTR correlated to longer OS as compared to PR/SBT (not reached vs 53.7 months, P=0.05), while no significant difference was seen in the pTERT-mutant group (37.0 vs 22.0 months, P=0.6).

To our knowledge, this is the first study that investigated the impact of the EOR according to EGFR amplification and pTERT mutation in IDH-wild type grade II astrocytomas: interestingly, EGFR-amplificated and pTERT-mutant patients did not seem to benefit from the EOR, differently from those with no such alterations.