Interstitial continuous infusion therapy in a malignant glioma model in rats

Division of Pediatric Neurosurgery, Children's Memorial Hospital, Chicago, IL 60614, USA.
Child s Nervous System (Impact Factor: 1.11). 03/2009; 25(6):655-62. DOI: 10.1007/s00381-008-0805-3
Source: PubMed


Local direct delivery of chemotherapeutic agents for the treatment of brain tumors is an area of focus in the development of new therapeutic paradigms. These techniques need improvement, especially in terms of drug retention in brain tissue.
In this study, we used a rat glioma model to examine carboplatin distribution, as measured by platinum penetration, after delivery via interstitial continuous (i.c.) infusion. We also examined rat survival times in response to carboplatin and oxaliplatin. I.C. infusion, a modified version of convection-enhanced delivery (CED) for local drug delivery, uses low volume (1 microl per hour) continuous infusion directly into the tumor.
I.C. infusion produced a nearly 360-fold higher concentration of platinum in tumor tissue and significantly prolonged rodent survival time compared to intraperitoneal (i.p.) infusion.
We showed i.c. infusion allows for circumvention of the blood-brain barrier, focused drug distribution, and sustained drug delivery. This method could be a promising strategy for treating brain tumors.

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