Clodronate Decreases Skeletal Morbidity in Patients with Bone Metastases from Breast Cancer: A Double-Blind Randomised Controlled Trial

Abstract

About 40% of patients treated with operable primary breast cancer will at some stage relapse and nearly half of these will have evidence of bone metastases at this time. Development of bone metastases depends in part on the release of osteolytic factors by tumour cells that are able to stimulate the host osteoclast to cause bone destruction. This facilitates the development of bone metastases and may produce the complications of bone pain, fracture and hypercalcaemia [1–3]. The development of bone metastases being dependent, particularly in the early phases, on recruitment of osteoclasts has raised the interest in use of agents which would inhibit osteoclastic bone resorption such as the bisphosphonates [4]. Oral clodronate has been shown to be an effective bisphosphonate for treatment of hypercalcaemia and malignancy [5], and there are indications that its long-term use may inhibit the effect of osteolysis caused by bone metastases [6]. Clodronate has the added attraction over other bisphosphonates of being effective by oral administration. The usual oral dose for efficacy is 1600 mg/day.