neurofibromatosis

my grandson age 7 years old, has had brown coffee stains on this body for a while.The Drs. said that most likely other members have it in the family. True, there are some , but lately he has it in more places, stomach, underarms, etc. the Dr wants him to be tested at the genetics clinic for von-recklinghausen"s neurofibromatosis. Please explain, what is that?? Does that have to do with the spine?? Thank you for your time,, answers can be written in Hebrew, but it was easier to explain in Eng. Sally,

http://www.nf.org/