The PSA test is a blood test that is Often carried out as a screening test to detect the presence of a swollen prostate and of prostate cancer. Though the test cannot in itself be used for diagnosis it is a good indicator and, in combination with other tests, PSA test can point to the need for additional investigation.

The PSA test is usually recommended for men in high risk groups (like those with a family history of the condition) once they reach the age of about 40 to 45 and for men in general after they reach the age of 50.

A single PSA test in isolation will give a snapshot of prostate specific antigen levels in the blood and might indicate a problem immediately if you have particularly high psa numbers. However, in most cases, and when a prostate problem may be in its early stages of development, a single PSA test result will prove to be inconclusive and a further test will normally be suggested in a few weeks time. In fact, ideally PSA testing should be carried out at regular intervals 2 or 3 times each year so PSA levels may be viewed over time.

Provided that you have a normal PSA score then all is well, but when your PSA levels begin to rise they must be monitored closely. The speed at which PSA levels rise is normally called the 'PSA velocity' and providing the rise is steady and the velocity slow then it is once again frequently sufficient simply to watch the situation as numerous things can influence levels of PSA and seemingly increasing levels will frequently fall back to normal given time.

However, when PSA levels begin to increase rapidly and the velocity is said to be high then further investigation is certainly necessary.

This pattern of PSA testing and monitoring has been performed for some time but, although the test has always been considered to be a good indicator of the need for additional investigation, it was not until quite recently that we have been in a position to link specific PSA velocity to prostate cancer in a way that can indicate how aggressive prostate cancer is.

In a study conducted recently data concerning 950 men with prostate cancer who had undergone either surgery of radiation treatment at four hospitals between 1988 and 2004 was carefully scutinized.

In all cases each patient had been diagnosed with aggressive prostate cancer on the basis of an isolated very high PSA score, a noticeable rise in PSA velocity during the year before diagnosis, an advanced stage tumor, a biopsy showing signs of an aggressive cancer at cellular level or a combination of two or more of these signs.

This study also looked at the post-treatment outcomes for all of the patients and found that a rapidly increasing PSA level that rose by 2 points or more in a twelve month period was the best indicator or an aggressive cancer.

Up until now we have been able to connect increasing PSA levels with the possible presence of prostate cancer but it has been necessary to guess to a fair degree about whether or not such a cancer might be aggressive and require correspondingly aggressive treatment.

However, now we are able to say with reasonable certainty that where a PSA level rises by 2 or more points in a twelve month period then prostate cancer is almost certainly aggressive and requires speedy and vigorous treatment.