Hypocalcemia in cancer.

Hypocalcemia based on total calcium measurement is frequent in certain cancers (especially prostate) in association with osteosclerotic bone metastases. In a majority of these patients hypocalcemia is related to the low serum albumin and/or renal failure. True ionized hypocalcemia may be seen as a toxic effect of certain chemotherapeutic agents or as a consequence of hyperphosphatemia due to rapid tumor lysis. In addition, tumors may produce osteoblast-stimulating factor(s) which cause massive accretion of calcium by the skeleton. Isolation and purification of these factors may provide us with unique osteoblast-stimulating factors which may have therapeutic applications.