What's the oldest age you can get a neuroblastoma?

Variable. Peak age is first three years of life. My oldest patient was nine years old.
Some adults. More than 90% of cases of this tumor occur in patients younger than 10 years; however, it has been reported in adults, though rarely. 54 yo individual is in literature.Adults with neuroblastoma have significantly worse outcome than children. This may be due to tumor biology, more virulent clinical course, or possibly due to the fact that adults are less sensitive or have poor tolerance to pediatric chemotherapy regimens.
97% Dx by 10yo. This is a tumor derived from nervous tissue & predominantly an issue of early childhood. 40% <3mo 90%<5yo and rare cases 3% listed as over 10y. The last large study i could find had 10-14yr as its oldest grouping.