title: [Oncogenic osteomalacia. Report of two cases].
abstract: Oncogenic osteomalacia is a rare disease. It is caused by a tumor that produces fibroblast growth factor 23, a hormone that decreases the tubular phosphate reabsorption and impairs renal hydroxylation of vitamin D. This leads to hyperphosphaturia with hypophosphatemia and low calcitriol levels. About 337 cases have been reported and we studied two cases; 44 and 70 year-old men who sought medical attention complaining of suffering diffuse bone pain over a period of approximately one year. In both cases, a laboratory test showed biochemical alterations compatible with a hypophosphatemic osteomalacia. In the first case, a soft tissue tumor of the right foot was removed, one year after the diagnosis. The patient was allowed to diminish the phosphate intake, but symptoms reappeared at this time. Eight years later, a local recurrence of the tumor was noted. A complete excision was now performed. The patient was able to finally interrupt the phosphate intake. In the second case, an F-18 fluorodeoxyglucose positron emission tomography, with computed tomography revealed a 2.26 cm diameter hypermetabolic nodule in the soft tissue of the right forefoot. After its removal, the patient discontinued the phosphate intake. Both patients are asymptomatic and show a regular phosphocalcic laboratory evaluation. The histopathological diagnosis was, in both cases, a phosphaturic mesenchymal tumor, a mixed connective tissue variant. This is the prototypical variant of these tumors.
authors: Servicio de Clínica Médica, Hospital Privado de Comunidad, Mar del Plata, Argentina. E-mail: fernandojerkovich@hotmail.com.
authors: Fernando
authors: F
authors: Jerkovich
authors: Daniel
authors: D
authors: Moncet
authors: Silvia
authors: S
authors: Babini
authors: Jorge A
authors: JA
authors: Zoppi
authors: Fabiana
authors: F
authors: Graciolli
authors: Beatriz
authors: B
authors: Oliveri
mesh_terms: D000328:Adult; D000368:Aged; D000089703:Fibroblast Growth Factor-23; D005346:Fibroblast Growth Factors / Q000302:isolation & purification; D005500:Follow-Up Studies; D005545:Forefoot, Human / Q000601:surgery; D006801:Humans; D008297:Male; D009364:Neoplasm Recurrence, Local; D009372:Neoplasms, Connective Tissue / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000473:pathology; D010018:Osteomalacia; D010257:Paraneoplastic Syndromes; D011877:Radionuclide Imaging; D035583:Rare Diseases / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000473:pathology
chemical_list: D005346:Fibroblast Growth Factors; D000089703:Fibroblast Growth Factor-23
keywords: fibroblast growth factor 23; hypophosphatemia; oncogenic osteomalacia; phosphaturic mesenchymal tumor