Overall survival after carmustine wafers implantation for newly-diagnosed high grade glioma. A nationwide population-based controlled propensity score-matched analysis

Objective

Widespread use of carmustine wafers (CW) for high-grade gliomas (HGG) has been limited by uncertainties about its efficacy. This study aimed to evaluate the overall survival (OS) of patients who underwent CW implantation after newly-diagnosed HGG resection.

Methods

In this retrospective study, we processed the French medico-administrative national database to retrieve ad hoc cases. Propensity score-matched (PSM) analysis was performed to reduce bias from confounding patient-related variables and, OS was compared between the two groups.

Results

A total of 2956 newly-diagnosed HGG patients who were post-operatively treated according the chemoradiotherapeutic Stupp regimen between the 1st January 2008 and the 31st December 2019 were extracted from the SNDS. 1518 (51.4 %) of these patients had CW implantation at HGG surgery. From the total recruited, 1604 (54.3 %) had missing data for at least 1 of the variables used to calculate the PS and, thus had to be excluded. Of the 1352 remaining subjects, we paired 500 treated patients with 852 controls. The median survival time for the treated group was 1.53 versus 1.42 years for the control group (p = 0.299). The estimated difference in restricted mean survival time between groups at 1, 2, 3 and 5 years were 0.02, _95 %CI[-0.02–0.05], p = 0.326; 0.06, _95 %CI[-0.04–0.16], p = 0.213; 0.11, _95 %CI[-0.04–0.27], p = 0.153 and 0.13, _95 %CI[-0.12–0.37], p = 0.322 respectively.

Conclusion

CW implantation with standard chemoradiotherapeutic treatment after newly-diagnosed HGG surgery did not increase the OS of patients.