Cerebrospinal fluid leak during treatment with bevacizumab and irinotecan after carmustine-impregnated wafers placement in patients with grade 2 oligodendroglioma and glioblastoma multiforme: report of two cases and review of literature.

Placement of carmustine-impregnated wafers has become a common practice after surgical resection of malignant gliomas. Bevacizumab is used as a second-line agent for the treatment of malignant gliomas and is sometimes used in patients who have had recent wafer implantation. We describe two cases of fatal cerebrospinal fluid (CSF) leak in patients treated with bevacizumab and irinotecan after 4 weeks of carmustine wafer implantation. Possible mechanisms for the CSF leak in these patients are discussed. We recommend waiting for a longer period of time before starting bevacizumab in patients who had implantation of carmustine wafers.