Few other cancers when they metastasise have such a variable natural course and effect on survival as breast cancer. Patients with hormone sensitive cancers may live for several years without any intervention other than various sequential hormonal manipulations. In contrast, patients with disease that is not hormone sensitive have a much shorter interval free of disease and shorter survival, reflecting the more aggressive biology of hormone independent cancers. The average period of survival after diagnosis of metastatic disease is 18-24 months, but this varies widely between patients. Clinical patterns of relapse predict future behaviour. Patients with a long interval without disease (more than two years) after primary diagnosis and favourable sites of recurrence (such as local lymph nodes and chest wall) survive longer than patients with either a short interval without disease or recurrence at other sites. Patients with visceral disease have the poorest outlook; these patients tend to have a short interval without disease and have cancers that are biologically more aggressive. FIG Median time of survival associated with sites of metastasis in patients with breast cancer. #### Hormonal treatment of metastatic breast cancer Premenopausal women Postmenopausal women Antioestrogens, aromatase inhibitors, and progestogens may be used in virtually any sequence in responsive patients. A patient may present with metastatic breast carcinoma or develop a systemic recurrence after treatment for an apparently localised breast cancer. The aim of treatment is to produce effective control of symptoms with minimal side effects. In terms of drug treatment this ideal is only achieved by hormonal treatment in the 30% of patients whose cancers respond to such drugs. There is …