title: Tumor-induced osteomalacia associated with a maxillofacial tumor producing fibroblast growth factor 23: report of a case and review of the literature.
abstract: Tumor-induced osteomalacia (TIO) is a rare acquired paraneoplastic disease characterized by renal phosphate wasting and hypophosphatemia. Recently, it was reported that tumors associated with TIO produce fibroblast growth factor (FGF) 23, identified as the last member of the FGF family and of which excessive action causes several hypophosphatemic diseases whereas deficient FGF23 activity results in hyperphosphatemic tumoral calcinosis. In this case, although it was difficult to locate the associated tumor, an abnormal mass in the left maxilla was detected by imaging. The tumor was removed by partial resection of the left maxillary alveolar region. Thereafter, serum level of FGF23 rapidly decreased, hypophosphatemia improved, and the clinical symptoms greatly improved. Histopathologic diagnosis of the tumor was phosphaturic mesenchymal tumor, mixed connective tissue variant. Immunohistochemical findings confirmed that the removed tumor produced FGF23. These results indicate that development of osteomalacia in this patient was related to the maxillary tumor, which overexpressed FGF23.
authors.affiliation: Department of Oral-Maxillofacial Surgery, Dentistry, and Orthodontics, University of Tokyo Hospital, Tokyo, Japan.
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Mori
authors.forename: Toru
authors.initials: T
authors.lastname: Ogasawara
authors.forename: Toru
authors.initials: T
authors.lastname: Motoi
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Shimizu
authors.forename: Daichi
authors.initials: D
authors.lastname: Chikazu
authors.forename: Kazumi
authors.initials: K
authors.lastname: Tamura
authors.forename: Seiji
authors.initials: S
authors.lastname: Fukumoto
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Takato
mesh_terms: D000328:Adult; D000089703:Fibroblast Growth Factor-23; D005346:Fibroblast Growth Factors / Q000009:adverse effects / Q000378:metabolism*; D005500:Follow-Up Studies; D006801:Humans; D017674:Hypophosphatemia / Q000097:blood / Q000209:etiology / Q000473:pathology; D008297:Male; D008441:Maxillary Neoplasms / Q000150:complications / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D008637:Mesenchymoma / Q000150:complications / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D009363:Neoplasm Proteins / Q000009:adverse effects / Q000378:metabolism*; D010018:Osteomalacia / Q000097:blood / Q000209:etiology* / Q000473:pathology; D010257:Paraneoplastic Syndromes / Q000209:etiology* / Q000473:pathology; D016896:Treatment Outcome
chemical_list: C000717427:FGF23 protein, human; D009363:Neoplasm Proteins; D005346:Fibroblast Growth Factors; D000089703:Fibroblast Growth Factor-23