Hi TheBedouin
Welcome to NeuroTalk

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I am sorry to read about your PN.
I would be very dubious about using the stem cell treatment you have been offered. Stem cells are widely used in treatment of some lymphomas and leukaemias but not yet for much else.
Stem cell therapies are very much at the experimental stages for some neurological conditions
The information here might help you.
Nine Things To Know About Stem Cell Treatments – A Closer Look at Stem Cells