What is the difference between “screening” and “testing” for prostate cancer?

As explained, “screening” means that people with no signs or symptoms of disease are urged to undergo a test to see if they have that disease. Because (except in rare circumstances) people cannot be compelled to be screened, governments sometimes mount large-scale public awareness campaigns designed to inform and persuade those people for whom screening is relevant to go to either a special screening service or to see their doctor (if the screening can be done in a doctor’s rooms). Essentially then, screening is testing people on a mass scale who have no symptoms of disease to see if indicators of disease may be present.

Those who try to distinguish “testing” from “screening” are in effect playing semantic games. Those urging that men be tested seldom use the term “screening”, but by directing the message at all men aged over 50, their intention is to effectively promote wholesale screening. They are in fact promoting screening but calling it “testing”. They are often aware of the long list of expert bodies (see p7) which have examined the wisdom of promoting screening and concluded that it is not a policy that should be promoted. But these groups are seeking to have it both ways by rejecting “screening” but supporting mass testing – in effect the same thing. A good example of this is 109the current policy of the Urological Society of Australia and New Zealand. Their policy states:

This policy is plainly having a bet each way. It agrees that screening all men is not a good idea for the reasons we explain in detail in this book (overdetection and overtreatment) but in the very next paragraph, states that PSA “testing” should be “offered” to men after age 55. This is simply a “Clayton’s” screening policy: promoting screening when you are not promoting it.

If women are screened for breast cancer, shouldn’t men be screened for “their” cancer too?

Women have their cancer screening tests (for cervical and breast cancer) and the Australian government recommends that all people 110aged over 50 be screened regularly for colorectal (bowel) cancer, so doesn’t it makes sense that men should be screened for prostate cancer?

In media coverage of the disease, men are repeatedly told they are not “being a man” if they don’t get tested. This is an argument frequently advanced by prostate screening advocates. Its subtext is that women are somehow more sensible about their health than men because more of them are attuned to regularly doing the sensible thing and checking for cancer. The simplistic logic runs that men should behave like women and line up to be tested too. This argument ignores any consideration of all the evidence that we have summarised, and ignores the rather important difference that the best available evidence shows a modest benefit of screening which must be weighed against the substantial risk of harm through overdiagnosis and overtreatment.

The parallel with mammography screening is an interesting one. Both PSA screening and mammography screening are double-edged swords. Both have a benefit (reduced chance of dying from cancer) and both have adverse effects which range from mild to severe. Like PSA screening we have evidence from randomised trials that mammography screening reduces women’s chances of dying from breast cancer. The effect is a little different, however, because breast cancer is a more common cause of death among women in their 40s, 50s and 60s than prostate cancer is among men in these age groups (as we have seen, most prostate cancer deaths occur in men aged over 70, and the average age of death from prostate cancer is almost 80). So compared to PSA screening, more relatively young women benefit from mammography screening.

Breast cancer screening has downsides too, just as we have seen with prostate cancer screening. A woman who has mammography 111screening may experience a false alarm by receiving an abnormal result on her mammogram which turns out not to be breast cancer, just like a man may get a high PSA level which turns out not to be prostate cancer. It may take several tests, often involving a biopsy, to confirm she does not have breast cancer. This can be very anxiety provoking.

More importantly, overdiagnosis and overtreatment are also problems with mammography screening. Strange though it may seem, a woman may be diagnosed with screen-detected breast cancer which is indolent and never destined to become life threatening. In fact it is estimated that about 25–30% of breast cancers found by screening may be like this [111, 112]. Because we can’t distinguish aggressive, life-threatening breast cancer from indolent breast cancer, all women diagnosed with breast cancer are offered treatment. In this way, the overdiagnosis becomes overtreatment. And as with prostate cancer, a diagnosis of breast cancer can have profound psychological effects, and treatments for breast cancer may have serious adverse physical effects.

With PSA screening, 12–50 extra men may be diagnosed with prostate cancer for each man whose death from prostate cancer is averted by screening. With mammography screening there is also a wide range of estimates about how many extra women are diagnosed with and treated for breast cancer. Some researchers estimate that two extra women are diagnosed with breast cancer for each woman whose death from breast cancer is averted by mammography screening. Others estimate 10 extra women are diagnosed with breast cancer for each woman whose death from breast cancer is averted [113]. This means, the balanace of benefits to harms of screening for breast cancer is better, as fewer extra women are treated to prevent each death from breast cancer. 112

Is improved treatment for prostate cancer responsible for decreasing death rates from prostate cancer?

As we demonstrated earlier, death rates from prostate cancer are now at about the same level that they were in the 1970s. In 1968 the age-adjusted death rate for prostate cancer was 35.6 per 100,000 and in 2007 it was 31 per 100,000 (see Table 4). This small difference follows the massive population-wide numbers of men who have been tested, investigated and treated for prostate cancer in this 39-year period. While it is possible that both improved treatment and screening with the PSA test are contributing to the decline in death rates observed since the early 1990s (i.e. from a high of 43.7 per 100,000 in 1993 to 31 per 100,000 in 2007), it seems clear that neither is having a very impressive impact.

Do male doctors and cancer experts themselves get tested for prostate cancer?

We know that smoking rates among doctors are the lowest in the population: in 1996, just 2% of Australian doctors admitted to smoking [114]. So do Australia’s male doctors aged over 50 also “take their own medicine” when it comes to being tested for prostate cancer? One 2002 study from Victoria has given us information on this. It found a minority – 45% – of doctors aged 49 or more had been tested [115]. By contrast, a 2006 US study found much higher levels of testing (95% of urologists and 78% of non-urologists) [116].

Who benefits from mass PSA testing in Australia?

One reason why so many men are now asking to be tested lies in the promotional activities of powerful commercial forces which strategically promote the benefits of testing but rarely talk about the major downsides. The US-based Us Too! International with 113325 worldwide groups is promoted as a “grassroots” organisation established and run by prostate cancer survivors wanting to assist men with making an “informed” choice. The Us Too! website lists a formidably long list of corporate sponsors in the pharmaceutical, medical equipment and pathology service industries [117]. All of these industries of course stand to benefit financially by large numbers of men being tested and investigated. It is thus predictable that the organisation recommends annual PSA tests for men, despite the controversies described in this book [118].

The strategy of drug and biotech companies supporting and funding apparently spontaneously created grassroots community groups of people living with a disease is known as “astroturfing”. Wikipedia describes astroturfing like this:

So when you hear about an organisation promoting prostate cancer screening, it is a good idea to try and investigate whether the 114organisation is sponsored by those who will benefit by large numbers of men getting tested.

In Australia, the Prostate Cancer Foundation’s website lists a large number of commercial sponsors of the Foundation. Among these are four pharmaceutical companies and the da Vinci company, which makes the robotic surgical machine discussed earlier. Each of the four pharmaceutical companies sells diagnostics (PSA tests) or drugs used to treat prostate cancer. That sounds like a natural and obvious coincidence of interests. The Foundation is dedicated to fighting prostate cancer and the companies have products that are involved in that fight. Well and good. But you will look in vain on the Foundation’s website or in any of its literature for any detailed explanation of the other side of the debate about prostate cancer screening that might cause some men to take pause.

To sum up

Prostate cancer is the second greatest cause of cancer death in Australian men after lung cancer. Like most cancers, it is a disease which is very uncommon to rare in men aged less than 50, although it does of course kill some men in their 40s and 50s. This alone will be news to many men who have heard about prostate cancer in the news and heard people saying that it can kill men young.

In fact, prostate cancer is a disease which – more than any other cancer – tends to kill men very late in life in the years in which men are at higher risk from dying per se (i.e. from any cause). Prostate cancer is one of the diseases that brings down the final curtain late in life in men. We all will die from some disease.

In 2010, the Prostate Cancer Foundation of Australia ran television ads featuring Australian male celebrities urging all men over 50 and men over 40 with a family history of the disease to get tested. The line-up included cricketers and footballers in their 30s. Underbelly 115actor Daniel Amalm, 31, was one of several young men who said on camera that prostate cancer can kill men “just like me”. But of the 75,433 men who died from prostate cancer between 1968 and 2007 in Australia, just two (0.003%) were aged 30–34. Given that no government anywhere in the world, no peak cancer control agency, and no high level, independent review of the evidence has to date supported screening, it is important to question campaigns like the Foundation’s and consider what it might achieve if it was wildly successful.

Prostate cancer screening advocates repeatedly emphasise that men need to make informed decisions about being tested. We wrote this book to provide men with information that is rarely included in “pro-screening” public information about prostate cancer.

Some incontestable information that you won’t find on the Prostate Cancer Foundation’s website nor in its TV ads is as follows.

First, prostate cancer is a disease that far more men die with rather than from. As we saw, we know this thanks to many autopsy studies where men who die suddenly or without having recently seen a doctor are examined for cause of death. At autopsy, 10–20% of men in their 50s and 40–50% in their 70s have prostate cancer but died from other causes. Many men who get tested will thus be found to have high PSA levels. Many will be then biopsied and counselled to have their prostates removed. This will stop them dying from prostate cancer, but the autopsy studies tell us that many of these men would not have died of prostate cancer even if their cancers had never been found. The problem is that there is no reliable way of knowing the benign from the deadly cancers, so overtreatment is rampant.

Second, prostate cancer tends to kill far later in life than other cancers. The average age of death for prostate cancer in Australia is 79.8 years, while the average age for all male cancers combined 116other than prostate cancer combined is 71.5 – considerably younger. More than half of men who die from the disease are aged 80 or over (average age of death for an Australian man in 2007 was 76 years, so men who die from any cause after that time are already living longer than average); and 82% are aged 70 or more. In 2007, just 2.8% (83 men) who died from the disease were aged less than 60, and 10 (0.1%) were in their 40s.

Men with family histories of prostate cancer are at elevated risk, but it follows that most of these men will have had fathers, uncles and grandfathers who died from the disease very late in life. If these relatives had not died from prostate cancer, many would have died within a few years from other causes because of their advanced age.

So, what’s the problem with men wanting to do all they can to avoid dying young, even if the odds are so low (the chance of a man aged 40–44 dying from prostate cancer in a year is a stratospheric one in 250,000 – worse odds than winning the lottery – while for men over 85 it is one in 125)? Thirty years ago, prior to PSA testing being available, our death rate from prostate cancer was 33.4 per 100,000 men. In 2007 it was 31 per 100,000, a decline of 7.2%. The decline probably reflects both early detection and better treatment. Yet over the same period, the incidence of prostate cancer rose 110% from 80.8 per 100,000 to 170 per 100,000, thanks to the aggressive promotion of PSA testing, often by those who stand to benefit financially by its proliferation.

The third major problem is that widespread testing leads to widespread unnecessary surgery and frequent serious complications. Recent data from across NSW show that three years after radical prostatectomy, 77% of men remain impotent and 12% have urinary incontinence compared to 22% and 1% respectively of age-matched men who do not have prostate cancer. Many of these men underwent unnecessary surgery and now live permanently with the consequences. They tend 117not to talk publicly about these problems. Trite dismissal of the daily lives of thousands of unnecessarily impotent and incontinent men by saying, “You can’t have sex in a coffin” is astonishingly arrogant. All this is why earlier this year Richard Ablin who discovered prostate-specific antigen on which the PSA test is based called the promotion of widespread testing “a hugely expensive public health disaster”.

In 2009, nine-year results were published from a multi-nation European trial of PSA testing. Dr Peter Bach from New York’s Sloan-Kettering Cancer Center summarised the meaning of the trial for a man being treated after testing positive today:

Enthusiasts for prostate testing emphasise that the European trial saved lives. It did. But the reduction was from 4.2 to 3.3 deaths per 10,000 person-years.

In 2010, further important results were published from a Swedish trial of prostate cancer screening. These results put a better complexion on the case for screening, finding that as few as 12 men would need to be treated to prevent one prostate cancer death in that population. But expert commentators on that study suggest that Sweden – a nation which has not had comparable proportions to Australia of men tested for prostate cancer – is not an ideal nation from which to draw lessons that would apply here.

Telling someone that they have cancer, particularly when the great majority of men thus diagnosed would have never died from the disease nor had their life in any way affected by the “silent” or indolent cancer inside them, can be deadly serious. We saw that a Swedish 118study found that the risk of suicide after diagnosis of prostate cancer was 7.4 times higher during the first week after diagnosis and 1.6 times higher during the first year after diagnosis, compared to age-matched men not diagnosed.

Some testing enthusiasts promote the idea that untested men are ignorant or in denial. But many men consciously choose to remain ignorant of their PSA status after reading widely for themselves. Indeed, a Victorian study of GPs aged over 49 found that 55% had not themselves been tested. Celebrities have made wonderful contributions to raising public health awareness, but this carries responsibilities to ensure the public are given the full picture. Promoting prostate cancer testing should emphasise both sides of the issue, to ensure men make fully informed decisions.

We hope that you found the information in this book useful and if so, would encourage you to send it to other men.

The book is available to download as a free PDF file at: hdl.handle.net/2123/6835