Subjective and metabolic effects of clodronate in patients with advanced breast cancer and symptomatic bone metastases.

Twenty postmenopausal women (aged between 46 and 67 years old) with skeletal metastases from breast carcinoma were treated with clodronate 450 mg i.v. daily for 5 days and thereafter with 100 mg i.m. daily for 10 days. All patients received standard hormonal therapy (tamoxifen). Symptomatic pain (evaluated according to a linear analog scale), performance status (according to Karnofsky), serum alkaline phosphatase, serum creatinine and osteocalcin were measured before and after treatment on days 5, 15, 30 and 45. Scanning by radiology were performed pre- and post-therapy. Bone pain was significantly reduced in 15 out of 20 patients. After clodronate treatment the base line value of circulating osteocalcin (3.2 +/- 1.6 ng/ml) showed a significant increase on days 30 and 45 (p less than 0.001). Radiological assessment of bone lesions showed stable disease in 18 patients and progression in two patients. No adverse side effects were observed. These data show that clodronate provided pain relief in 75% of treated patients and the increase in circulating osteocalcin levels can be considered a marker of the stabilization of skeletal metastatic lesions.