Hypercalcemia Caused by PTH-rP Associated with Lung Metastasis from Urinary Bladder Carcinoma: An Autopsied Case.

Abstract

We analyzed the parathyroid-related protein (PTH-rP) content in tissue specimens obtained from a 61-year-old man with hypercalcemia associated with lung metastasis from urinary bladder carcinoma using radioimmunoassay and immunohistochemistry. Radioimmunoassay showed that the PTH-rP content was higher in metastatic lung tumor tissue than in non-tumorous lung tissue. Immunohistochemical analysis revealed the presence of PTH-rP in tumor cells. Furthermore, proliferation of osteoclasts was found in bone marrow at autopsy. The results suggest that PTH-rP induced humoral hypercalcemia of malignancy in a patient with urinary bladder cancer.