Although there is a trend toward earlier detection of prostate cancer, unfortunately many men are not diagnosed until the disease has progressed to a later stage. When cancer spreads to neighbouring tissues or to other parts of the body such as the bones, this is called advanced (metastatic) prostate cancer or secondary cancer. It can take many months or years before prostate cancer spreads to other parts of the body.
If prostate cancer spreads beyond the prostate region, hormone therapy is usually the first line of treatment. Hormone therapy, also called androgen deprivation therapy (ADT), can slow or stop the growth of prostate cancer by preventing the production of testosterone which prostate cancer cells usually depend on for growth.
The success of hormone therapy in controlling prostate cancer varies between men and may be effective for many months or years. In fact, more than 80% of men who receive this treatment benefit, this is reflected in a reduction in prostate specific antigen (PSA) levels.
There are two main approaches to hormone therapy are:
- A surgical procedure to remove the testicles
- Medication in the form of tablets or injections that minimise the effect or ‘switchs off’ of testosterone in the body.
When prostate cancer no longer responds to hormone therapy and growth of the cancer continues, it is called hormone resistant or hormone refractory prostate cancer. This occurs if cancer cells do not need testosterone for growth. If prostate cancer becomes hormone resistant, a range of therapies aimed at treating or slowing the progression of symptoms can be provided.
Treatments for locally advanced prostate cancer resistant to hormone therapy include chemotherapy, palliative radiotherapy, oestrogen treatment and bisphosphonates in cancer.
Chemotherapy
Reduces prostate specific antigen (PSA) levels and significantly extends the lifespan of men with advanced (metastatic) prostate cancer that is resistant to hormone therapy.
Palliative radiotherapy
External beam radiotherapy is usually administered and up to 80% of men treated will experience rapid pain improvement.
Oestrogen treatment
Introducing a low dose oestrogen hormone plus aspirin may lower prostate specific antigen (PSA) levels by suppressing the production of testosterone.
Bisphosphonates in cancer
Bisphosphonates in cancer work to delay loss of bone density.
Like other medicines, treatments for advanced prostate cancer can have both benefits and side effects – these vary between men.