I think people are confusing benign prostatic hyperplasia (aka benign prostatic enlargement) and prostate cancer. The two are often confused but they are distinctly different.
Benign prostatic hyperplasia is generally diagnosed by a rectal examination and the symptoms are urgency, slow stream and difficulty in emptying the bladder. In BPH the prostate enlarges and puts pressure on the bladder & urethra. It is treated with drugs and/or surgery depending on severity.
Prostate cancer develops silently and whilst it is contained inside the prostate (localised prostate cancer) it usually has no symptoms. It is true that many prostate cancers grow slowly and the man is likely to die from some other cause before the cancer is a real issue. However some do develop quickly and once it has spread outside the prostate it is a serious, and life threatening, problem. The 5-year survival rate for those where the cancer has spread to bone, organs or lymph nodes is as low as 30%.
Diagnosing prostate cancer is quite difficult:
In a digital rectal exam the doctor may be able to feel irregularities of the surface of the prostate indicating cancer but it is easily confused with BPH. Also you cannot feel all the way around the prostate from the rectum.
A PSA blood test measures the amount of prostate specific antigen in your blood, a raised PSA may indicate cancer but it is an inexact measure and can be influenced by other factors, such as having sex or vigorous exercise close to the test. A raised PSA does not necessarily mean it is cancer and you can have prostate cancer but still have a very low PSA. So there are a lot of false positives & negatives.
In some hospitals you may be offered a multi-parametric MRI but this is in its infancy and the correlation between what is on the MRI scan and whether it is cancerous can only by confirmed by biopsy and histology to stage & grade the cancer.
There is no national screening programme for prostate cancer.
