Hypercalcemia due to parathyroid hormone-related protein produced by primary ovarian clear cell adenocarcinoma: Case report

Objective. Among ovarian carcinomas, clear cell adenocarcinoma is one of th e most common histologic subtypes associated with hypercalcemia. However, t he mechanisms of hypercalcemia in clear cell adenocarcinoma are still uncle ar. In the following case report, we tried to determine the etiology of hyp ercalcemia and also to demonstrate the management of hypercalcemia diagnose d preoperatively. Case. A 49-year-old woman was diagnosed as having a malig nant ovarian tumor with hypercalcemia caused by elevated serum parathyroid hormone-related protein (PTHrP) prior to her primary surgery. Treatment wit h disodium incadronate promptly normalized the serum calcium level. An immu nohistochemical study demonstrated PTHrP expression in the primary ovarian lesion, but not in the metastatic lesion. A Northern blot analysis of the c ancer cells from the ovarian tumor confirmed the presence of PTHrP mRNA, Co nclusion. Humoral hypercalcemia of malignancy in this case has been conclus ively shown to be due to the production of PTHrP at the primary ovarian tum or, based on both immunohistochemical and molecular analyses. (C) 2000 Acad emic Press.