By definition, the diagnosis of POEMS syndrome is confirmed when both the polyneuropathy and monoclonal plasma cell disorder are present in association with one of the other three major criteria: Castleman disease, sclerotic bone lesions, and vascular endothelial growth factor elevation, and one of the six minor criteria: organomegaly, extravascular volume overload, endocrinopathy, skin changes, papilledema, thrombocytosis, or, polycythemia. This evidence concerns the gene VEGFA and polyneuropathy.