The pathogenic tumor secretes so-called phosphatonins [3], such as fibroblast growth factor 23 (FGF23) [4], frizzled related protein-4 [5], matrix extracellular phosphoglycoprotein [6] and FGF7 [7], which causes reduced reabsorption of phosphate in the proximal renal tubule. The gene discussed is FGF23; the disease is neoplasm.