[Hypercalcemia and neoplasms: recent advances in pathogenesis].

The mechanisms of paraneoplastic hypercalcemic syndromes are heterogeneous. Neoplastic hypercalcemia without bone metastatic disease is caused by parathyroid hormone related protein, whose action is comparable to parathyroid hormone. Growth transforming factors, platelet derived growth factor, tumor necrosis factors and interleukin 1 are also involved in humoral hypercalcemia of malignancy. In addition to these substances, hypercalcemia in bone metastatic disease may be related to PGE. Tumor necrosis factors and interleukin 1 play a major role in multiple myeloma as well as in Adult T cell Leukemia/Lymphoma where overproduction of vit D3 by lymphomatous cells can also be significant.