Clinical diagnosis and treatment of tumor-induced osteomalacia: An analysis of 11 cases

Objective To improve the clinical diagnosis and treatment level of tumor-induced osteomalacia (TIO) by analyzing the clinical features, diagnosis and treatment of 11 cases with TIO. Methods Clinical data (including clinical presentation, management, perioperative clinical status and biochemical changes) of 11 patients with TIO admitted to our hospital from April 2010 to April 2013 were retrospectively analyzed. Results There were 5 males and 6 females with an average age of 37.7 years (range 19-54 years). The average time interval between onset and proven TIO was 5.5 years (range, 2-15 years). All the 11 patients presented with bone pain and muscle weakness, hypophosphatemia, hyperphosphatemia, normal serum calcium and increased alkaline phosphatase (ALP). Subcutaneous soft tissue mass was found in 3 cases, ^99mTc-OCT was performed in another 8 cases and it showed high expression of somatostatin receptor on different lesions of different patients. All the patients were confrmed by histopathology after operation. Serum Pi levels returned to normal in 10 patients after resection of tumors, symptoms of bone pain and muscle weakness were all improved obviously. Conclusion TIO is an extremely rare acquired disease with typical clinical features. Identifying the responsible tumors is clinically essential for the treatment of TIO, ^99mTc-OCT and other imaging examinations are also helpful to locate the tumors. After complete excision of the tumors, the patients' serum phosphate levels and clinical symptoms are greatly improved.