Prostate cancer happens when abnormal cells develop and grow in the prostate. These abnormal cells can continue to multiply in an uncontrolled way and sometimes spread outside the prostate into nearby or distant parts of the body.
In most men, prostate cancer is a slow growing disease. If it stays inside the prostate gland and grows slowly, it may never cause a problem.
However, in some men the cancer may grow more quickly and can cause problems that can impact on their life expectancy.
When the cancer cells spread outside of the prostate to other parts of the body, it is known as advanced or metastatic prostate cancer.