Utilization of palliative radiotherapy for breast cancer patients with bone metastases treated with bisphosphonates-Toronto Sunnybrook Regional Cancer Centre experience.

Abstract

The use of both bisphosphonates and palliative radiotherapy for the prevention and treatment of skeletal complications in women with bone metastases from breast cancer is well established. We undertook an evaluation of palliative radiotherapy utilization rates in breast cancer patients who received bisphosphonates for the treatment of bone metastases in a major Canadian cancer center. Charts and electronic files of breast cancer patients with bone metastases who had received either clodronate or pamidronate at any time between January 2000 and December 2001 at our center were retrospectively reviewed. The utilization rates of palliative radiotherapy in these patients were examined. The percentage of patients receiving bisphosphonates for the treatment of bone metastases who also received palliative radiotherapy to bone remained relatively constant over our study period in the range of 70%. In patients commenced on bisphosphonates before 1998, 42.9% received palliative radiotherapy as initial therapy for bone metastases, whereas in 2001 only 27.8% of patients received palliative radiotherapy before commencing bisphosphonate therapy. There has been a marked improvement in the time between the diagnosis of bone metastases and the commencement of bisphosphonates from a median of 446 days before 1998 to 21 days in 2001. At the same time, there was also an improvement in time between diagnosis of bone metastases and initiation of palliative radiotherapy from a median of 265 days before 1998 to 49 days in 2001. Use of bisphosphonates has not reduced the utilization rates of palliative radiotherapy in breast cancer patients with bone metastases. There is a trend of initiating bisphosphonates before delivery of palliative radiotherapy. The latter was also delivered earlier in the course of bone metastases.