[1] Washington Univ, Sch Med, Dept Neurol, St Louis, MO 63110 USA
[2] Washington Univ, Sch Med, Dept Radiat Oncol, St Louis, MO 63110 USA
[3] Washington Univ, Sch Med, Dept Pathol & Immunol, St Louis, MO 63110 USA
[4] Washington Univ, Sch Med, Dept Neurosurg, St Louis, MO 63110 USA
[5] Univ Dusseldorf, Dept Neuropathol, D-4000 Dusseldorf, Germany
[6] Univ Texas, MD Anderson Canc Ctr, Dept Pathol, Houston, TX 77030 USA