Retraction Note to: J Neurooncol (2009) 94:87–96 DOI 10.1007/s11060-009-9807-6

This article published in, Volume 94, Issue 1, pages 87–96, DOI 10.1007/s11060-009-9807-6, has been retracted, as it contains portions of other authors’ writings on the same topic in other publications, without sufficient attribution to these earlier works being given. The principal authors of the paper acknowledged that text from background sources was mistakenly used without proper reference to the original source.