Chemotherapy is generally only used to treat prostate cancer that has spread outside of the prostate.
Several chemotherapy drugs can be used, but the most effective is Docetaxel (Taxotere), which is also used in the treatment of breast cancer.
Taxotere was approved by the National Institute of Clinical Excellence (NICE) in June 2006 for advanced prostate cancer that is not responding to hormone therapy. Your Oncologist/Urologist should be able to give you more information on this treatment option and whether it is suitable for your treatment.