Aims and background: Symptomatic relief of bone metastases with biphosphonates has been previously reported, but limited data are available on the possibility of the induction of sclerosis in osteolytic lesions.
Methods: We therefore initiated an open study with disodium pamidronate (45 mg infused over 1 h and repeated every 21 days) in patients with bone metastases from breast cancer pretreated with chemotherapy and/or hormonetherapy. Fourteen patients with measurable lytic or mixed bone disease entereted the study. No other systemic therapy for breast cancer was allowed after their inclusion in the study.
Results: No radiologic evidence of bone sclerosis of lytic disease was seen. After 2 months of therapy, 9 patients had progressed and 5 had stable disease. The median time to progression of bone disease was 1.6 months (range, 1-9). No significant improvement in terms of symptomatic status or analgesic consumption was recorded. The treatment was well tolerated, and no significant local or systemic toxicity was observed.
Conclusions: Disodium pamidronate at a dose of 45 mg every 3 weeks is not capable of inducing sclerosis of lytic lesions from pretreated breast cancer. Further trials concentrating on higher dosages of disodium pamidronate are warranted.