Intracerebral delivery of Carboplatin in combination with either 6 MV Photons or monoenergetic synchrotron X-rays are equally efficacious for treatment of the F98 rat glioma

Abstract

Background: The purpose of the present study was to compare side-by-side the therapeutic efficacy of a 6-day infusion of carboplatin, followed by X-irradiation with either 6 MV photons or synchrotron X-rays, tuned above the K-edge of Pt, for treatment of F98 glioma bearing rats. Methods. Carboplatin was administered intracerebrally (i.c.) to F98 glioma bearing rats over 6days using AlzetTM osmotic pumps starting 7days after tumor implantation. Radiotherapy was delivered in a single 15Gy fraction on day 14 using a conventional 6 MV linear accelerator (LINAC) or 78.8keV synchrotron X-rays. Results: Untreated control animals had a median survival time (MeST) of 33days. Animals that received either carboplatin alone or irradiation alone with either 78.8keV or 6 MV had a MeSTs 38 and 33days, respectively. Animals that received carboplatin in combination with X-irradiation had a MeST of>180days with a 55% cure rate, irrespective of whether they were irradiated with either 78.8 KeV synchrotron X-rays or 6MV photons. Conclusions: These studies have conclusively demonstrated the equivalency of i.c. delivery of carboplatin in combination with X-irradiation with either 6 MV photons or synchrotron X-rays. © 2012 Bobyk et al.; licensee BioMed Central Ltd.