Phosphaturic mesenchymal tumor

Phosphaturic mesenchymal tumor is a benign neoplasm of mesenchymal origin, that produces phosphatonin (fibroblast growth factor 23). This tumor may cause tumor-induced osteomalacia, a paraneoplastic syndrome, by the secretion of phosphatonin, which has phosphaturic activity (by inhibition of renal tubular reabsorption of phosphate and renal conversion of 25-hydroxyvitamin D to 1,25-dihydroxyvitamin D).