Cancer-Related Hypercalcemia

Hypercalcemia has been reported to occur in up to 30% of patients who have a malignancy. Hypercalcemia is most common in those who have later-stage malignancies and predicts a poor prognosis for those with it. The most common causes include humoral hypercalcemia of malignancy mediated by parathyroid hormone–related peptide, osteolytic cytokine production, and excess 1,25-dihydroxy vitamin D production. However, the etiology is not always mediated by malignancy. Hypercalcemia can occur in those with malignancy and an additional etiology for hypercalcemia such as primary hyperparathyroidism or granulomatous diseases. This paper reviews the cancers associated with hypercalcemia and their proposed mechanisms, nontumor-mediated hypercalcemia, as well as diagnosis and treatment strategies for each condition.