[Bisphosphonates, pain and quality of life in metastatic breast cancer patients: a literature review].

Bisphosphonates constitute the standard treatment for cancer hypercalcemia and prevention of complications of metastatic bone disease. Various clinical endpoints have been used to evaluate the impact of bisphosphonates on bone metastases. This literature review is focused on the analgesic effect of bisphosphonates and their impact on quality of life (QoL) in patients with bone metastases from breast cancer. Twenty-five randomized trials studying bisphosphonates with pain and/or QoL as primary or secondary endpoints were considered. These studies were analyzed with following criterias : study type, primary cancer, drug scheduling, number of patients included, associated specific treatment, primary and secondary endpoints, pain assessment, and QoL assessment. The results are in favor of an efficacy of bisphosphonates in bone pain, even when not always statistically significant and with an important variability in assessment criterias and tools. QoL assessment with validated, reliable scales (EORTC QLQ-C30, Rotterdam Symptom Checklist...) has been performed in 9 studies. The use of bisphosphonates with systemic and radiation therapy increases QoL or reduces QoL deterioration. Despite some methodological limitations, these studies indicate a beneficial effect on bone pain, and an improvement in the QoL of patients with metastatic bone disease of breast cancer. Because of a lack of systemic data, reliable analysis of the results is difficult. Several questions remain open about which bisphosphonates and route of administration to choose, and the variable effects on different primaries.