I'm sorry to hear about your son. As soon as I have an epassporte payment in I'll send what I can.
I've actually been doing a lot of alternative medical research lately and I recently found treatments that seem to be pretty successful.
Here are a few links that I have bookmarked. Their are children about your sons age on the survivors site that are doing quite well using the PolyMVA.
http://www.polymva.com
http://www.polymvasurvivors.com
Here is another with lots of good information:
http://www.mnwelldir.org/docs/cancer1/altthrpy.htm
Please stay away from Chemo if it's suggested. It does nothing for these types of tumors, and will drain the life out of whoever messes with it.