Neuroblastoma and protein losing enteropathy (PLE) are diagnoses commonly seen by oncologists and gastroenterologists, respectively. The concurrence of these 2 entities is rare, and not well explained. We describe the sixth case of PLE in a child with neuroblastoma, and the first for which genetic information is available. Tumor DNA had a mutation in the PTPN11 gene, which has been described in neuroblastoma, and in Noonan syndrome-a diagnosis in which neuroblastoma and PLE independently have been reported. Constitutional DNA was normal. Genetic studies in future patients will be needed to support the link between neuroblastoma and PLE.