Hypercalcemia and Ectopic Secretion of Parathyroid Hormone by an Ovarian Carcinoma with Rearrangement of the Gene for Parathyroid Hormone

Abstract

HYPERCALCEMIA accompanied by elevated serum concentrations of parathyroid hormone (PTH) is the cardinal feature of primary hyperparathyroidism. The excessive production of PTH is due most often to a parathyroid adenoma, less often to parathyroid hyperplasia, and rarely to parathyroid carcinoma. In contrast, humoral hypercalcemia of cancer is now recognized to be a syndrome that is not dependent on PTH. Levels of the novel peptide PTH-related peptide are increased in the serum of most patients with squamous carcinoma,1 and through its binding to a common receptor for PTH and PTH-related peptide, it produces the biochemical features of hyperparathyroidism.2 Immunoradiometric assays for . . .