Reduction in the cerebrospinal fluid protein level after bevacizumab treatment in patients with optic pathway low‐grade gliomas

Abstract

Optic pathway gliomas (OPG) can cause elevated cerebrospinal fluid (CSF) protein concentrations. We report on two patients with suprasellar low-grade gliomas and high CSF protein levels (590 and 551 mg/dl) that precluded shunt implantation. After two and three doses of bevacizumab, respectively, the levels dropped dramatically to 191 and 178 mg/dl, respectively. Bevacizumab treatment was associated with a decrease in CSF protein level, allowing successful shunt placement. Our results are consistent with the pharmacological mechanism of bevacizumab, which decreases protein leakage from blood vessels to the ventricles.