What causes hypercalcemia?
Hypercalcemia of malignancy has many causes. It may be related to the spread of cancer from its site of origin to bones in the body, a process called metastasis. Cancer cells can spread, or metastasize, through the blood and lymph systems. A cancer cell may break away from the original location in the body and travel in the circulatory system until it gets lodged in a small capillary network in bone tissue. Cancer may also spread to bone from the adjacent cancer, though this occurs less frequently than spread by the blood stream. Bone metastases result in injury to the bone tissue.Although bone appears to be the most static of all the tissues in the body, it is actually very dynamic and active. Normal bone is constantly being remodeled, or broken down and rebuilt. Every week humans recycle 5% to 7% of their bone mass. As much as half a gram of calcium may enter or leave the adult skeleton each day.One important function of bone remodeling is maintenance of blood calcium levels. Calcium
