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Posts Tagged ‘US and Western European prostate studies’

MAY 11: PROSTABLOG NZ:  Anyone doubting the significance of the two long-term prostate cancer testing studies just published in the US need only read a NZ Medical Journal paper published late last year by leading Kiwi urologist Robin Smart.

He accurately predicted the studies “may or may not” resolve debates about national screening and making more information available to GPs and patients.

The studies have had mixed reviews, but, as Smart says, they add to a vast body of knowledge that overwhelmingly supports the value of PSA, digital examination and biopsy testing.

He laments a lack of technology and promotion of information about testing in NZ that could save up to half the 600 men who currently die of proistate cancer here each year, a figure that is static, compared to big improvements in Western Europe, the US and Australia.

He says our government’s antagonistic attitude to prostate cancer information dissemination puts us with the backward practices of Eastern Europe, where adoption of modern methods and testing (including PSA), has resulted in increasing death rates.

He points out that statistics quoted to rebuff calls for national screening are well below those accepted for NZ breast and cervical cancer screening programmes.

His conclusions (full paper available to NZ Medical Journal subscribers only):

“An overwhelming body of evidence shows that PSA/digital rectal examination testing leading on to TRUS (ultrasound) biopsy and curative treatments (where indicated) has been a major advance for men’s health.

Indeed, those with significant experience of dealing with men with this cancer in pre-PSA times appreciate the difference only too well.

Then, 70% had metastases at diagnosis and the mortality ratio was 41%.

Studying the fate of control group men in the various trials outlined above, especially those in Bill-Axelson and Holmberg’s trial, provides a chilling reminder of the potential for this cancer to ruin or end a man’s life in his later years.

It is true that these improvements in morbidity and mortality have come at a price of more investigation and treatment. Numbers of men diagnosed with prostate cancer have approximately doubled.

But this is the inevitable price for better results. The first-line investigations of PSA, DRE, and TRUS biopsy have been shown to be well tolerated and safe in an office setting.

It is important that men with insignificant cancer, or major comorbidity, or limited projected lifespan, get appropriate management, including surveillance only or other minimal approaches. It is also important that men with threatening cancers get these recognised in time for curative treatment.

A special group are those with a family history of prostate cancer. The usual lifetime risk of 12% doubles if one first-degree relative has prostate cancer and increases by 5 to 7 times if more than one has it.  Therefore, potential benefit of PSA testing includes not just the individual but also his family, and there is evidence that the outlook for family members is improved by PSA/DRE testing.

Before PSA testing, the outlook was worse for those with a family history compared to the general population but now it is better. This is considered to be due to a greater awareness and earlier testing by relatives of those with prostate cancer.

The dramatic improvements in morbidity and mortality from prostate cancer in Western Europe, North America, and Australia outlined above have occurred because a very large proportion of the middle aged and older men in those countries have undergone PSA and DRE testing.

The drive for this remarkable change has occurred at community level amongst men, their families, and family doctors on learning about this technology as a way to avoid advancing prostate cancer.

Governments generally have been neutral or antagonistic about PSA testing.

For example, the British National Health Service states: “Opportunistic screening (with PSA) should be discouraged” and the New Zealand Guidelines Group (NZGG) in 2004 stated several times in its information for practitioners that PSA “Not recommended as a screening test in asymptomatic men.”

New Zealand has not shared the improvements in prostate cancer mortality experienced by other advanced Western nations including Australia detailed above. Rather, our annual mortality has been static at about 600, similar to eastern European countries.

Large numbers (more than 2000) of men are now diagnosed with prostate cancer in New Zealand each year. But there have been powerful discouragements to men contemplating PSA testing and their family doctors resulting in uncertainty and confusion.

This includes not just the efforts of the NZGG, but also studies originating in the New Zealand Ministry of Health critical of general practitioners screening with PSA and DRE.

Many general practitioners are ambivalent about it as a result. Some have adapted by only referring on men with higher PSAs, for example 8 or more. This author’s experience has been that the most recent 300 TRUS Biopsies have a mean referral PSA of 11.1, and the last 100 radical prostatectomies—a mean referral PSA of 8.4.

Others actively discourage PSA testing and disseminate that view.

A common argument used is that 450 men must be screened to save 1 from dying of prostate cancer (a figure which is disputed)—and that this is too large to make screening worthwhile.

But the equivalent figure for breast cancer screening is 1700, and that for cervical cancer screening 8000. It seems likely that New Zealand men have not been tested as much, and perhaps sometimes been referred later (compared to men in Australia, North America, and Western Europe), to explain the difference.

Access to investigations and treatments may be poorer in New Zealand than the other countries, especially for the two-thirds of the population without health insurance.

Of course, most New Zealand general practitioners exercise great care in dealing with this issue.

The NZGG this year (2008) formed an ‘advisory group’ comprising representatives of the Prostate Cancer Foundation, radiation oncologists, urologists (including this author), the Cancer Society, the College of Pathologists, general practitioner, and Maori to formulate more information material.

The “non-Ministry” members of this group strongly favoured the NZGG providing men contemplating PSA/DRE testing with information about the advances discussed above, including changes internationally in prostate cancer mortality and trials. It was considered that men making such a decision at this time were entitled to this information.

The institution of a national screening programme was not advised, but provision of this information to men was.

But the draft containing this advice was rejected, the NZGG citing its contract with the Ministry and opting for neutrality. An opportunity [was] lost to improve prostate cancer results in New Zealand as has occurred in other countries.

To be fair to the NZGG, other government authorities internationally have adopted a similar neutral or opposing stance. And, as with any field of human endeavour, papers continue to be published expressing scepticism about PSA/DRE screening.

The long-awaited analysis of the ERSPC and PLCO trials, already put off from 2008 for a few years, and which have cancer mortality as end points, may resolve the debates. Or may not. There are many potential problems with these huge multicentre trials, not least of which is occult cross over from control to PSA groups. Initial results, as discussed above, support PSA/DRE testing.

The weight of evidence in favour of PSA/DRE testing is now overwhelming after almost two decades of international experience. To go back to the time before PSA testing would now be unthinkable.

Of course we hope for the perfect tests, perfect treatment, and continue to look for improvements. But New Zealand men today need the benefit of current technology which the evidence shows could save between 200 and 300 of the 600 who currently die of prostate cancer each year.

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