Renal handling of calcium and sodium in metastatic and non-metastatic malignancy.

Investigation of the renal handling of calcium and sodium in rehydrated patients with hypercalcaemia associated with malignancy showed enhanced reabsorption of calcium in most cases. This was a feature of both metastatic and non-metastatic malignancy, and in this respect the patients were indistinguishable from patients with primary hyperparathyroidism. As the increased calcium reabsorption was inversely correlated with the rate of excretion of sodium modest salt loading can be used to inhibit this process. This is an important practical aspect of the treatment of patients with this type of hypercalcaemia.