Osteomalacia cured by surgery.

Oncogenic osteomalacia is an uncommon syndrome characterized by bone pain, proximal muscle weakness, hypophosphatemia, hyperphosphaturia, and a low concentration of 1,25-dihydroxyvitamin D. This syndrome is induced by a tumor, usually benign, of mesenchymal origin and resolves after its excision. We report a case of an oncogenic osteomalacia caused by a small mesenchymal tumor of the tendon sheath of the foot, a localized form of tenosynovial giant cell tumor.