Resolution of Severe Oncogenic Hypophosphatemic Osteomalacia after Resection of a Deeply Located Soft-Tissue Tumour

Abstract

Oncogenic osteomalacia is a rare metabolic bone disease characterized by phosphate leakage from the kidney and subsequent hypophosphatemia. It is caused by a phosphaturic factor produced by certain tumours. removal of such tumours can completely cure the condition. Here, we report the case of a patient who was crippled with oncogenic osteomalacia. Extensive study revealed a tumour deeply located in the pelvis; removal of the tumour resulted in complete recovery. The tumour was identified as a mesenchymal tumour (mixed connective-tissue variant). The diagnostic evaluation, differential diagnosis, and treatment are discussed.

Phosphaturic Mesenchymal Tumor

“…28 Although local recurrence may occur, surgical resection is considered curative in approximately 90% of cases. 27,29 Cryoablation has been successfully used to treat residual tumor after resection. 30 For patients with unresectable tumors, a fully human monoclonal antibody against FGF23, burosumab, has been shown to provide biochemical and symptomatic improvement and was FDA-approved.…”

Preoperative evaluation and orthopedic surgical strategies for tumor-induced osteomalacia

“…Metastases of the PMT were diagnosed and the patient underwent chemotherapy. Succumbed to respiratory failure due to relapsing lung metastases and disseminated intravascular coagulation / PMTMCT; metastases from the PMT with malignant transformation Radaideh AR [64] 2009 39,M Low back pain for 3 years. A few months later, he developed limping on the left leg Persistent hypophosphatemia 0.6 mmol/L (normal range: 0.81–1.6 mmol/L) A three-phase 99 Tc bone scan Medially to the left psoas muscle 5 × 1.2 × 1 cm The tumor was resected Complete resolution 3 years PMTMCT Nelson AE [65] 2003 52,M Fracture of the right third metatarsal and multiple rib fractures after gym exercise Hypophosphatemia Whole body bone scintigraphy; Plain radiography; Whole body scintigraphy with octreotide In the right superior pubic ramus 2.7 × 2.7 × 4 cm Excision biopsy; removal of the angiolipoma; surgically removed en bloc Complete resolution 12 months A benign angiolipoma François S [66] 1997 10,M Diffuse bone and muscle weakness for two years Phosphorus was very low (0.43 mmol/l) Radiograph In the left superior pubic ramus NA Complete tumor resection and the space was filled with bone graft Complete resolution NA Benign mesenchymal tumor Note: M: male; F: female; PMT: phosphaturic mesenchymal tumor; PMTMCT: phosphaturic mesenchymal tumor, mixed connective tissue variant; NA: none; CT:computed tomography; MRI: magnetic resonance imaging; PET/CT: Positron emission tomography/computed tomography.…”