How would you manage a multiply recurrent intramedullary pilocytic astrocytoma following re-resection?

For a conventional pilocytic astrocytoma, the Ki-67 index is typically <2–5%, with values above 10% being unusual. A recurrence with a MIB of 15% raises the possibility of a more biologically aggressive tumor, even if the histologic diagnosis remains pilocytic astrocytoma. As such, I would want to k...