Prostate cancer is one of the most common cancer in New Zealand men.  Doctors do not know the exact cause of prostate cancer, however, there are likely to be genetic and environmental factors.   Men with a first degree relative with prostate cancer (brother, father) have a 2 to 3 times increased risk, with two or more relatives the risk rises to at least  5 times.  It is known that prostate cancer growth is highly influenced and stimulated by male hormones, particularly, Testosterone.

It is thought dietary factors may increase risk (animal fat), and possibly reduce risk (Vitamin E, selenium, lycopenes in cooked tomatoes), although this is still largely speculative and research with large trials is ongoing. More evidence is accumulating that obesity is a risk factor in men.

Many men who experience urinary symptoms including poor urine flow, urinary urgency, dribbling after voiding, don’t necessarily have prostate cancer, but are most likely to have benign prostate enlargement, infection or inflammation.  In advanced stages of prostate cancer and/or metastatic spread of prostate cancer, patients can begin to experience the bothersome urinary symptoms discussed above.   If you are experiencing any of the symptoms listed above it is important to discuss these with your doctor to ensure you are not at risk for prostate cancer.



The most sensitive and specific test to diagnose prostate cancer is the PSA blood test.  The accuracy of the blood test is improved when combined with the findings of the prostate examination (DRE).


PSA is a substance produced by the prostate.  It does “spill over” into the blood stream.  The higher the PSA level the higher the risk of prostate cancer.  A rapid increase in PSA or a steadily climbing PSA can also be factors for your doctor to consider having you evaluated by a Urologist. Prostate cancer is not the only reason that doctors see elevated PSA.

Other reasons for an elevated PSA are:

  1. Benign prostate enlargement – this is the natural enlargement of the prostate that occurs when men get older.
  2. Inflammation or infection of the prostate.


Commonly adopted age adjusted PSA levels are:
< 50 years       0 – 2.5

50 – 60 years    0 – 3.5

60 – 70 years    0 – 4.5

over 70 years    0 – 6.5