Background/Aims: Hypercalcemia is a paraneoplastic syndrome that is a serious condition requiring urgent treatment. We administered alendronate to hypercalcemia patients with advanced cancer with metastasized liver tumors or hepatocellular carcinoma (HCC) and then evaluated the mechanism and anticancer function of this compound.
Methodology: We retrospectively studied 17 patients with hypercalcemia associated with metastatic liver tumor or HCC. Alendronate (10mg) was administered via the intravenous route for patients with metastatic liver tumor (n=12) and via the hepatic artery for patients with HCC (n=5).
Results: Intravenous administration of alendronate resulted in decrease in serum calcium levels in all patients. The serum levels of tumor markers also decreased in 66.7% (8/12) of these patients. After intra-arterial alendronate administration, the serum calcium and parathyroid hormone-related protein levels decreased in all the patients. The serum levels of tumor markers such as AFP and PIVKA-II were decreased in 80% (4/5) of these patients. Electron microscopic examination of the resected hepatic tumor revealed an increase in the vascularization and formation of apoptotic vesicles in the vascular endothelial cells.
Conclusions: Alendronate is effective not only for controlling hypercalcemia but also for directly enhancing the apoptosis of HCC cells.