Patterns of bone metastasis and their prognostic significance in patients with carcinoma of the prostate.

The different patterns of bone metastasis, metastatic load and their prognostic significance were examined in a consecutive series of 169 men with prostatic cancer and bone metastasis at presentation. Patients with an isolated metastasis in the pelvis or dorsal vertebrae had a better prognosis than those whose metastases were either diffuse or involved more distal sites such as the skull or the sternum, although all of these patients were classified as having M1 disease. Bone metastasis involving an area equivalent to 1 vertebral body equalled a metastatic load of 2. Based on their total metastatic load, 3 prognostic groups were identified with significant differences in case-specific survival despite receiving the same hormonal treatment. When comparing the potential efficacy of various treatments one must stratify the metastatic load, which is a powerful prognostic indicator of the outcome in patients with metastatic carcinoma of the prostate.