Advice on a recurrent medulloblastoma

Hi,
I'm contacting you about a little 5 years old boy (my nephew in law) who is suffering from a recurrent medulloblasma.
The details are the following:
In Octobre 2008 a standard-risk medulloblastoma was diagnosed. The tumor has been totally removed by a neurosurgeon intervention by Professor Constantini and has been treated according
the protocol COG –ACNS 0331 that includes radiotherapy 55.4 Gy in the rear side and 23.4 Gy in CSI and chemotherapy (cisplatin, CPM, CCNU,VCR). He received the treatment completely without particular complications. The treatment has been completed in November 2009.
Unfortunately, in late January 2010, a MRI followed by a biopsy show some metastases in the lateral ventricules.

The medical team does not really propose a treatment for him, they are hesitating around experimenting an aggressive method that includes HDCT with stem cell rescue but they are not really optimistic.

I don't have any medical education and I do not fully understand the details I'm providing to you now. As a member of the family, I'm looking for a maybe more experimental method that could be effective in the case we are dealing with.

We need urgently some help and/or advices,

Thank you a lot,

Michael