Tumoral calcinosis: A metabolic disease of obscure etiology

Abstract

The clinical course and results of calcium, phosphorus and nitrogen balance, radiocalcium kinetics and electron microscopy in a case of tumoral calcinosis are presented, with a review of the relevant literature. Rapid exchange of calcium between the serum and the masses and increased intestinal absorption of dietary calcium have been demonstrated. No defect in skeletal calcium turnover was noted. Although the exact cause remains unclear, elevated levels of serum phosphorus and the frequent occurrence among siblings suggest that tumoral calcinosis may be an inborn error of metabolism. The structural characteristics of the masses in the case reported here indicate that inflammation or degeneration are local factors involved in the pathogenesis and or progression of tumoral calcinosis. Cells lining the spaces are structurally and apparently functionally similar to osteoblasts and osteoclasts.