Hyperphosphatemic tumoral calcinosis: a 10-year follow-up

Abstract

Objective: To report a case of primary hyperphosphatemic tumoral calcinosis (TC) and its long-term 10-year follow-up.

Patient: The patient was an 18-year-old male, who had been diagnosed with TC at the age of 8 years. In spite of nine surgeries for tumoral resection and medical treatments (i.e., aluminum hydroxide, non-steroidal anti-inflammatory agents) the lesions continued to progress. Physical examination showed calcified masses on shoulders, hip, elbows and right foot. PTH, calcitonin, 25(OH) vitamin D, 1,25(OH)₂ vitamin D, renal and liver function, electrolytes, alkaline phosphatase, calcium and magnesium were normal. Serum phosphorus was elevated. FGF-23 (C-terminal): 1960 RU/mL (<180) Radiological and histological studies were compatible with TC.

Conclusion: This long-term follow-up illustrates the morbidity and difficulty in treating these patients due to the progressive and recurrent nature of the calcified masses, for which there is no effective treatment as yet. The discovery of FGF-23 as the factor responsible for the hyperphosphatemic type of TC paves the way for forthcoming therapies.