There are two main conditions that affect the prostate gland that can cause problems for men as they get older; benign (non-cancerous) swelling of the prostate gland which is very common and prostate cancer. Fortunately the majority of men that present with a change in the pattern of their urination do not have cancer however there are similarities with the symptoms of both conditions.
Here is a link to a very useful explanation around how prostate cancer is checked for:
It is important to note that there is not a specific one off blood test for prostate cancer, assessing your risk is a combination of taking account of your symptoms, often a blood test and usually an examination, this is something your GP will be able to discuss in more detail.
Also there is not a ‘screening’ program for prostate cancer, unlike with breast and cervical cancers, this is because there is not a reliable enough test to allow this to happen, more information about this can be found here: