ABSTRACT
Quite why breast cancer has such a propensity to spread to bone is not fully established, but almost certainly it is a dynamic dependent on the microenvironment of bone and the biological characteristics of breast cancer cells. Bone is a dynamic organ, actively maintained in a healthy state to permit a good quality life. Traditionally, bone metastases are seen as less important than visceral disease, with a low-key palliative approach often being taken in terms of endocrine therapy and occasional radiotherapy. However, the degree of dysfunction, pain and loss of motility that can be consequent upon bone metastases is considerable. It remains a common site of disease, occurring in up to 75% of all patients with advanced breast cancer, and eventually appearing in around onethird of all patients presenting with early, operable, breast cancer. It might be considered less important as rapid progression is less common than in visceral disease; however, the recent improvements in survival from metastatic disease may be greater in those with hormone-sensitive disease, a group which includes the majority of patients with bone metastases. Therefore as our systemic treatments get better, more patients live longer with bone metastases, so that to an extent they can become the major source of morbidity and resource utilisation of patients with metastatic breast cancer.
