Conventional treatment of hypercalcemia of malignancy.

Treatment of hypercalcemia of malignancy (HCM) is briefly reviewed, available treatments are compared, and treatment guidelines are presented. The most effective strategy is treatment of the underlying malignancy. For patients who have a poor prognosis and no viable treatment options, the most humane course may be no treatment at all since encephalopathy will cloud their consciousness. Patients with mild hypercalcemia (corrected serum calcium concentration < 12 mg/dL) may respond to oral hydration, salt restriction, and ambulation, which encourage the normal bone remodeling process. Patients with moderate (corrected serum calcium concentration 12.0-13.5 mg/dL) to severe (> 13.5 mg/dL) hypercalcemia may require rehydration with 0.9% sodium chloride injection. Furosemide may be indicated to counteract fluid overload from rehydration measures or in patients at risk of developing congestive heart failure. For patients with renal failure not caused by dehydration, dialysis with a calcium-free or low-calcium solution is the treatment of choice. The calciuric effect of rehydration lasts only two to three days, and antiresorptive therapy is indicated for patients who require a longer duration of effect. Calcitonin is useful if a rapid decrease in serum calcium is necessary, but tachyphylaxis limits its use. Corticosteroids should be used only in patients with tumors that produce 1,25-dihydroxycholecalciferol. The use of plicamycin is limited because of adverse effects. Before the availability of zolendronic acid, pamidronate disodium was the treatment of choice, because of its longer duration of action than etidronate disodium and potential safety advantages. Zolendronic acid (discussed elsewhere in this supplement) is likely to supercede pamidronate disodium as the drug of choice for HCM, but the presence of symptoms, the rate of rise in serum calcium concentration, and the overall status of the patient are important considerations in selecting therapy.