Hypercalcemia in Patients Treated with Oral Bisphosphonates for Tumor-Induced Osteolysis

Michał Holecki

doi:10.3889/mjms.1857-5773.2013.0322

Abstract

Objective: Hypercalcemia as the consequence of an excessive bone resorption is a common complication in patients with cancer. The aim of the study was to analyze the prevalence of hypercalcemia in patients with tumor-induced osteolysis starting therapy with bisphosphonates.Methods: The questionnaire-based survey (data collected during three consecutive examinations within a 3-month period) was conducted among 1,450 patients treated with bisphosphonates for tumor-induced osteolysis.Results: Hypercalcemia was found in 8.7% respondents starting the treatment with bisphosphonates. The most common cause of malignancy-associated hypercalcemia was prostate cancer, multiple myeloma and breast cancer. On the other hand, hypercalcemia was the most prevalent among patients with multiple myeloma, metastatic cancer of an unknown primary origin and bladder cancer. Metastases were reported in 342 patients, while pathological fractures in 37. The normalization of calcium level was obtained in 91.4% of the patients treated with bisphosphonates, mostly clodronate. During the bisphosphonate therapy, pathological fractures occurred in 4.6% of patients and the percentage of the patients reporting bone pain decreased from 79.9% to 30.9%.Conclusion: Multiple myeloma, prostate and breast cancer are the most common causes of hypercalcemia of malignancy in patients with tumor-induced osteolysis starting therapy with bisphosphonates.

Highlights

Hypercalcemia resulting from an excessive bone resorption is a common complication in patients with advanced cancer, and the malignancy is the most common cause of hypercalcemia in clinical practice [1]
There are three major cancers contributing to the development of hypercalcemia: multiple myeloma (MM), T-cell lymphoma and breast cancer [2,3,4]
The primary mechanism of hypercalcemia in the patients with cancer is an increased bone resorption resulting from tumor secretion of cytokines, PTH-related peptide (PTHrp) and calcitriol [5]

Summary

Introduction

Hypercalcemia resulting from an excessive bone resorption is a common complication in patients with advanced cancer, and the malignancy is the most common cause of hypercalcemia in clinical practice (approximately 70% of cases) [1]. The primary mechanism of hypercalcemia in the patients with cancer is an increased bone resorption resulting from tumor secretion of cytokines, PTH-related peptide (PTHrp) and calcitriol [5]. Bone pain is the most common clinical sign of increased tumor-induced osteolysis, reported by approximately 60% of patients [6]. The use of bisphosphonates is the treatment of choice in patients with tumor-induced osteolytic hypercalcemia. The drugs bind to the surface of hydroxyapatite, inhibit osteoclast-mediated bone osteolysis ( decreasing calcium release and formation), inhibit maturation of osteoclasts (by inducing their apoptosis), reduce the loss of bone mineral mass and the risk of bone fractures and have an analgesic effect [7,8,9]

Methods

Results

Conclusion