The Neuropharmacokinetics of Temozolomide in Patients with Resectable Brain Tumors: Potential Implications for the Current Approach to Chemoradiation
- 11 November 2009
- journal article
- clinical trial
- Published by American Association for Cancer Research (AACR) in Clinical Cancer Research
- Vol. 15 (22), 7092-7098
- https://doi.org/10.1158/1078-0432.ccr-09-1349
Abstract
Purpose: Intracerebral microdialysis (ICMD) is an accepted method for monitoring changes in neurochemistry from acute brain injury. The goal of this pilot study was to determine the feasibility of using ICMD to examine the neuropharmacokinetics of temozolomide in brain interstitium following oral administration. Experimental Design: Patients with primary or metastatic brain tumors had a microdialysis catheter placed in peritumoral brain tissue at the time of surgical debulking. Computerized tomography scan confirmed the catheter location. Patients received a single oral dose of temozolomide (150 mg/m2) on the first postoperative day, serial plasma and ICMD samples were collected over 24 hours, and temozolomide concentrations were determined by tandem mass spectrometry. Results: Nine patients were enrolled. Dialysate and plasma samples were successfully collected from seven of the nine patients. The mean temozolomide areas under the concentration-time curve (AUC) in plasma and brain interstitium were 17.1 and 2.7 μg/mL × hour, with an average brain interstitium/plasma AUC ratio of 17.8%. The mean peak temozolomide concentration in the brain was 0.6 ± 0.3 μg/mL, and the mean time to reach peak level in brain was 2.0 ± 0.8 hours. Conclusions: The use of ICMD to measure the neuropharmacokinetics of systemically administered chemotherapy is safe and feasible. Concentrations of temozolomide in brain interstitium obtained by ICMD are consistent with published data obtained in a preclinical ICMD model, as well as from clinical studies of cerebrospinal fluid. However, the delayed time required to achieve maximum temozolomide concentrations in brain suggests that current chemoradiation regimens may be improved by administering temozolomide 2 to 3 hours before radiation. (Clin Cancer Res 2009;15(22):7092–8)Keywords
This publication has 29 references indexed in Scilit:
- Percutaneous Implantation of Cerebral Microdialysis Catheters by Twist-Drill Craniostomy in Neurocritical Patients: Description of the Technique and Results of a Feasibility Study in 97 PatientsJournal of Neurotrauma, 2006
- Metabolic Manipulation of Glioblastoma in Vivo by Retrograde Microdialysis of L-2, 4 Diaminobutyric Acid (DAB)Journal of Neuro-Oncology, 2006
- Intensive insulin therapy reduces microdialysis glucose values without altering glucose utilization or improving the lactate/pyruvate ratio after traumatic brain injury*Critical Care Medicine, 2006
- In vivo microdialysis for PK and PD studies of anticancer drugsThe AAPS Journal, 2005
- Radiotherapy plus Concomitant and Adjuvant Temozolomide for GlioblastomaThe New England Journal of Medicine, 2005
- Metabolic Crisis without Brain Ischemia is Common after Traumatic Brain Injury: A Combined Microdialysis and Positron Emission Tomography StudyJournal of Cerebral Blood Flow & Metabolism, 2005
- Distribution of BPA and metabolic assessment in glioblastoma patients during BNCT treatment: a microdialysis studyJournal of Neuro-Oncology, 2005
- Extracellular lactate and glucose alterations in the brain after head injury measured by microdialysisCritical Care Medicine, 1999
- Phase I trial of temozolomide (NSC 362856) in patients with advanced cancer.1997
- Extracellular hippocampal glutamate and spontaneous seizure in the conscious human brainThe Lancet, 1993