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 the most common histologic subtypes associated with hypercalcemia. However, the mechanisms of hypercalcemia in clear cell adenocarcinoma are still unclear. In the following case report, we tried to determine the etiology of hypercalcemia and also to demonstrate the management of hypercalcemia diagnosed preoperatively. Case. A 49-year-old woman was diagnosed as having a malignant ovarian tumor with hypercalcemia caused by elevated serum parathyroid hormone-related protein (PTHrP) prior to her primary surgery. Treatment with disodium incadronate promptly normalized the serum calcium level. An immunohistochemical study demonstrated PTHrP expression in the primary ovarian lesion, but not in the metastatic lesion. A Northern blot analysis of the cancer cells from the ovarian tumor confirmed the presence of PTHrP mRNA, Conclusion. Humoral hypercalcemia of malignancy in this case has been conclusively shown to be due to the production of PTHrP at the primary ovarian tumor, based on both immunohistochemical and molecular analyses. (C) 2000 Academic Press.