Hypercalcemia

Elevated blood calcium. The most common cause is the production of a biochemical substance by tumors, resulting in the retention of calcium. This is called pseudohyperparathyroidism, most commonly occurring in patients with lymphoma or tumors of the apocrine anal sac. Pseudohyperparathyroidism has been reported associated with other tumor types. Primary hyperparathyroidism occurs uncommonly. Elevation of blood calcium.