The condition and the treatment(s)
When prostate cancer has spread to another part of the body, it is called advanced or metastatic prostate cancer. In most men with prostate cancer, the hormone testosterone makes the cancer grow faster. So prostate cancer can be treated with drugs that make the body produce less testosterone, or react to it in a different way. This is called androgen deprivation treatment
After a time, the cancer stops responding to such treatments – this is known as 'hormone‑relapsed' cancer.
Enzalutamide (Xtandi) is another drug that works by stopping testosterone from getting to the cancer cells. Chemotherapy is used to control metastatic prostate cancer that is not responding to hormone therapy, and can reduce symptoms.
NHS Choices may be a good place to find out more.