- A phase II window trial of procarbazine and topotecan in children with high-grade glioma: a report from the children's oncology group. Chintagumpala, M.M., Friedman, H.S., Stewart, C.F., Kepner, J., McLendon, R.E., Modrich, P.L., McCluggage, C., Burger, P., Holmes, E., Thompson, S., Rutka, J., Michalski, J., Woo, S., Blaney, S.M., Kun, L.E., Horowitz, M.E. J. Neurooncol. (2006)