Ganglioglioma is a non cancerous tumour that arises from ganglion cells in the central nervous system. I would try to answer the questions one by one. 1. There is no way to reduce it using medicines and surgery is the only option. 2. Since it is non cancerous, you can wait, but I would not suggest you to do so. You need not worry about the age of the child. Till it is operated, it will affect brain functions and may cause seizures. So, earlier the surgery, the better. 3. Since the tumour has affected the hippocampus which plays important roles in the consolidation of information from short-term memory to long-term memory and spatial navigation, the child could develop some problem in remembering on short term or long term basis and also may have some problems with spatial orientation. However, let me assure that a child s brain is plastic and the functions get redistributed quickly and so the chances of such loss will decrease the earlier the surgery is done. 4. Although it is possible for seizures to come even after the surgery, the frequency will be less and it will probably resolve entirely with time.