[Oncogenic osteomalacia: the role of the phosphatonins. Diagnostic usefulness of the Fibroblast Growth Factor 23 measurement in one patient].
BACKGROUND
Oncogenic osteomalacia (OO) is a rare paraneoplastic syndrome characterized by severe hypophosphatemia induced by phosphaturic factors which are secreted by some tumors of mesenchymal origin. Fibroblast Growth Factor 23 (FGF-23) belongs to this family. Measurement of FGF-23 might improve the diagnosis of OO.


METHODS
We report the case of 71-year-old Caucasian man who had a history of severe osteomalacia with multiples fractures and extreme hypophosphatemia with hyperphosphaturia and normal serum calcium level. Serum FGF-23 was 199 RU/ml (N < 100 RU/ml). The tumor, detected by F-18 FDG PET/CT SCAN was localized in the mandible. Surgical removal of the tumor relieved all symptoms with normalization of serum phosphate levels within 3 days after surgery.


CONCLUSIONS
We conclude that FGF-23 measurement is likely to be of considerable importance for facilitating early diagnosis of OO.
Dupond
J L
JL
Service de médecine interne, hôpital Jean-Minjoz, boulevard Fleming 25030 Besançon cedex, France. jean-louis.dupond@ufc-chu.univ-fcomte.fr
Magy
N
N
Mahammedi
M
M
Prie
D
D
Gil
H
H
Meaux-Ruault
N
N
Kantelip
B
B
D000368:Aged; D015415:Biomarkers / Q000032:analysis*; D000089703:Fibroblast Growth Factor-23; D005346:Fibroblast Growth Factors / Q000097:blood*; D050723:Fractures, Bone / Q000209:etiology; D006801:Humans; D008297:Male; D008334:Mandible / Q000473:pathology; D010018:Osteomalacia / Q000175:diagnosis* / Q000209:etiology*; D049268:Positron-Emission Tomography
D015415:Biomarkers; C000717427:FGF23 protein, human; D005346:Fibroblast Growth Factors; D000089703:Fibroblast Growth Factor-23