Tumor-Induced Osteomalacia: Increased Level of FGF-23 in a Patient with a Phosphaturic Mesenchymal Tumor at the Tibia Expressing Periostin

Table 1

Laboratory data of the patient before and after resection of the giant cell tumor.

Laboratory value (normal range)	Before resection	2 days after resection	2 months after resection	26 months after resection	29 months after resection	Last follow-up, 34 months after resection
FGF-23 c-terminal (0.026–0.110 RU/mL or 20–70 pg/mL	0.396 (+)	0.037 (normal)	Normal	Normal	Normal	Normal
Phosphate (2.6–4.5 mg/dL)	1.95 (−)	n.p.	Normal	Normal	2.14 (−)	Normal
Calcium (8.5–10.1 mg/dL)	Normal	Normal	Normal	Normal	Normal	Normal
Alkaline phosphatase (40–129 U/L)	305 U/L	276 U/L	178 U/L	Normal	Normal	Normal
Bone specific alkaline phosphatase (<75%)	79.6%	n.p.	n.p.	n.p.	Normal	Normal
1.25-(OH)2D (16–81 pg/mL)	4.83 (−)	n.p.	Normal	Normal	Normal	Normal
25-(OH)-D (20–60 ng/mL)	21 (normal)	n.p.	17.3 (−)	Normal	Normal	Normal
Parathyroid hormone (15–65 ng/L)	Normal	Normal	Normal	Normal	Normal	Normal

n.p. = not performed.