This study by R.E. Coleman and R.D. Rubens reviews the clinical course of bone metastases from breast cancer, focusing on incidence, prognosis, morbidity, and response to treatment. Key findings include: - **Incidence and Prognosis**: Bone metastases were the most common site of metastatic disease, affecting 69% of patients dying with breast cancer. Bone was also the most frequent site of first distant relapse, occurring in 47% of patients. The median survival for patients with disease confined to the skeleton was 24 months, compared to only 3 months after first relapse in the liver. - **Tumour Characteristics**: Bone metastases were more common in receptor-positive or well-differentiated (grade 1) tumours. Liver metastases were more likely to occur in receptor-negative or poorly differentiated tumours. - **Response to Treatment**: The response to primary endocrine therapy and chemotherapy in bone was less than the overall response. Many patients had static disease, reflecting the insensitivity of UICC assessment criteria. Survival was similar between responding and non-responding patients, suggesting that tumor response may occur without visible radiological improvement. - **Hypercalcaemia**: Hypercalcaemia was a common complication, affecting 10% of patients. All patients with hypercalcaemia had metastatic disease, and 85% had widespread skeletal involvement. - **Management**: Various treatments were used, including hormone therapy, chemotherapy, and surgical interventions for complications such as pathological fractures and spinal cord compression. The study highlights the need for new approaches to treatment and more accurate assessment methods to improve management. The study underscores the clinical importance of bone metastases, their long and symptomatic course, and the challenges in assessing treatment responses.This study by R.E. Coleman and R.D. Rubens reviews the clinical course of bone metastases from breast cancer, focusing on incidence, prognosis, morbidity, and response to treatment. Key findings include: - **Incidence and Prognosis**: Bone metastases were the most common site of metastatic disease, affecting 69% of patients dying with breast cancer. Bone was also the most frequent site of first distant relapse, occurring in 47% of patients. The median survival for patients with disease confined to the skeleton was 24 months, compared to only 3 months after first relapse in the liver. - **Tumour Characteristics**: Bone metastases were more common in receptor-positive or well-differentiated (grade 1) tumours. Liver metastases were more likely to occur in receptor-negative or poorly differentiated tumours. - **Response to Treatment**: The response to primary endocrine therapy and chemotherapy in bone was less than the overall response. Many patients had static disease, reflecting the insensitivity of UICC assessment criteria. Survival was similar between responding and non-responding patients, suggesting that tumor response may occur without visible radiological improvement. - **Hypercalcaemia**: Hypercalcaemia was a common complication, affecting 10% of patients. All patients with hypercalcaemia had metastatic disease, and 85% had widespread skeletal involvement. - **Management**: Various treatments were used, including hormone therapy, chemotherapy, and surgical interventions for complications such as pathological fractures and spinal cord compression. The study highlights the need for new approaches to treatment and more accurate assessment methods to improve management. The study underscores the clinical importance of bone metastases, their long and symptomatic course, and the challenges in assessing treatment responses.