Why do we carry on screening?

The surprising thing about the widespread reporting last week of a new study – showing that the Prostate Specific Antigen test does not contribute to an increased life expectancy in men who have it – was that it was considered newsworthy at all (1).

This study simply confirms the results of numerous similar studies over the past decade (2). After a series of reviews of the evidence, both the UK National Screening Committee and the US Preventive Services Task Force have repeatedly rejected proposals for national PSA screening. The most recent US task force judgement was that ‘screening is associated with important harms, including frequent false-positive results and unnecessary anxiety, biopsies and potential complications of treatment of some cancer that may never have affected a patient’s health’ (3).

At a conference of the American Urological Association in 2004, Thomas Starney, Professor of Urology at Stanford, reported on a study showing that the PSA test was no more than a measure of the size of the prostate (4). He observed that, though PSA levels were of some value in monitoring the progress of prostate disease, they were of little diagnostic value and had led thousands of American men to have their prostates removed unnecessarily. Starney declared that ‘the PSA era is over’.

Not in my surgery it isn’t. Despite all the evidence against using PSA as a screening test and the reservations of all the official screening bodies, men still come trooping in asking for PSA tests. These tests are provided as a routine – together with numerous other useless investigations – in the course of ‘check-ups’ provided by private health insurance organizations (5). It is estimated that the number of men having a PSA test in Britain each year is more than 100,000 and rising. The demand for PSA parallels the popularity of other screening tests for cancer, such as ‘breast self-examination’ and ‘testicular self-examination’, which numerous expert bodies have advised against (on the grounds that they create anxiety and misdiagnosis out of all proportion to benefit). Though there is considerable expert scepticism about the diagnostic value of cervical smears and mammograms, this has done nothing to dampen demands to extend these programmes.

Why are people so willing to subject themselves to screening tests that offer scant benefits yet carry significant risks of harm?

One factor in the popularity of PSA testing is that it is backed by powerful commercial forces which assiduously promote its benefits. One prominent campaigning group, Us Too! International – which is based in the USA with branches in other countries, including several in the UK – describes itself as a ‘grassroots’ organisation set up by prostate cancer survivors. A glance at its website reveals that it is ‘supported by an unrestricted educational grant’ from Abbott Oncology, a pharmaceutical company that produces, not only PSA testing kits, but a range of drugs for prostate cancer (6). Given that Us Too! derives 95 per cent of its income from the pharmaceutical industry it is not surprising to find that it recommends annual PSA tests for men (7).

Similar ‘astro-turfing’ techniques (the laying of artificial ‘grassroots’) have been identified in relation to other screening controversies (mammography, bone scanning for osteoporosis), as well as in fostering demand for particular drug treatments (8). The drug companies are skilful in using celebrity sponsorship and providing human interest stories for newspapers and television stations which have an insatiable appetite for disease, particularly cancer.

Yet neither commercial nor medical influences can explain the dramatic rise in the demand for PSA testing in recent years. Both these factors are relatively weaker in the UK than in the USA, yet British men are flocking in for their PSA tests. No doubt, drug companies and doctors are beneficiaries of increased awareness of prostate cancer (and cancer in general), but men have not been frogmarched into surgeries to have blood tests (let alone ‘digital rectal examination’). To explain why men have responded with such enthusiasm to the promotion of screening tests we have to turn to the changing attitudes towards health and disease in society in general, and among men in particular.

To any individual worried about their health, the great attraction of screening tests is the promise ‘early detection, better outcome’. This has a great commonsensical appeal, reflected in popular convictions such as that ‘if only he had reported those symptoms earlier, he would be still alive today’. Unfortunately, in relation to prostate cancer, there is little evidence to support this conviction, or the associated notion that picking up the disease through a screening test even before symptoms are apparent guarantees an even better prognosis. The real problems of prostate cancer are that its natural course is not well understood (it is, for example, difficult to distinguish between forms that are aggressively malignant and those that pursue a relatively benign course) and that no current form of treatment (surgery, chemotherapy, hormone therapy) has been shown to prolong life (though they may greatly impair its quality).

One of the options recommended by oncologists in relation to the diagnosis of prostate cancer is ‘watchful waiting’ – that is to defer treatment of uncertain value and wait to see how the disease evolves. Though ‘watchful waiting’ is the course of action carrying the least risk of adverse side-effects (such as incontinence and impotence), it still carries the curse of increased cancer awareness, brought home by a raised PSA result. You will not live any longer, or any healthier, but under a cloud of fear of the future.

Individual attitudes towards cancer screening are powerfully influenced by the contemporary cultural climate in which cancer awareness campaigns have acquired a prominent position. The most successful of these are the breast cancer campaigns which have won a high public profile with mass participation events, such as fun runs and marches, with celebrity sponsors, badges and ribbons and dedicated days and weeks of promotional activities. In some ways, these campaigns seem to have taken the place of the protest movements of the past: instead of demonstrating against unemployment or war, people now march to raise awareness of disease.

These campaigns provide role models of ‘survivors’ – distinguished by their commitment to ‘fighting’ cancer, in relation to their own condition, and in overcoming public ignorance about the condition. The identity of ‘cancer survivor’ echoes that of political militant, though this new identity is conferred by a biological misfortune rather than a process of personal and political development. Activist survivors are among the most enthusiastic promoters of screening tests, offering their personal experience as a vindication of the procedure.

Campaigns around prostate cancer follow the lead of the breast cancer campaigns in the same way that the men’s health movement apes the earlier feminist movement. In fact, in its early radical phase, the women’s movement regarded the world of medicine as patriarchal and oppressive and attempted to organise key aspects of women’s healthcare autonomously. However, once the radical moment passed, this movement was rapidly incorporated by the medical establishment. What started out as a challenge to medical authority over women contributed to the evolution of a more comprehensive system for the medical regulation of women’s lives – notably in the spheres of pregnancy and childbirth and in the promotion of screening tests of dubious efficacy such as cervical smears and mammography.

Lacking any radical impulse, the men’s health magazines have taken the degraded end product of the women’s health movement as their model. Far from challenging medical authority, they urge men to submit themselves to it on a greater scale than ever before. In choosing campaigning issues, advocates of men’s health have proceeded by analogy with the feminists: they had cervical smears – we demand prostate examinations; they can do breast self-examination – we can play pocket billiards.

The parallel between screening tests for cervical and prostatic cancer is richly symbolic. Just as the smear test exposes women not merely to the medical gaze, but also to vaginal penetration, so the palpation of the prostate involves digital penetration of the male rectum. The slippery finger may be less impressive than the metal speculum, but it is no less significant as an instrument of symbolic domination.

The rising demand for PSA testing is a potent symbol of the ascendancy of disease over health and death over life in contemporary culture.

Dr Michael Fitzpatrick is author of The Tyranny of Health: Doctors and the Regulation of Lifestyle, Routledge, 2000 (buy this book from Amazon UK or Amazon USA), and MMR and Autism: What Parents Need to Know (buy this book from Amazon (UK) or Amazon (USA)).

Read on:

The dangers of prostate testing, by Dr Liz Frayn

Why awareness is bad for your health, by Dr Michael Fitzpatrick

Doctors on the defensive, by Dr Michael Fitzpatrick

(1) The Effectiveness of Screening for Prostate Cancer: A Nested Case-Control Study, John Concato et al, Arch Intern Med. 2006;166:38-43.

(2) Walter W Holland and Susie Stewart, Screening in Disease Prevention: what works? Nuffield Trust/European Observatory on Health Systems and Policies, Radcliffe Press, 2005.

(3) Guide to clinical preventive services, Agency for Healthcare Quality and Research

(4) End of the PSA in the USA?, Men’s Health Forum

(5) A picture of health, Margaret McCartney, Weekend FT, 7 January 2006

(6) Us Too

(7) Lenzer, J, ‘Lay campaigners for prostate screening are funded by industry’, BMJ 2003; 326: 680

(8) Ray Moynihan, Alan Cassells, ‘Selling Sickness: How Drug Companies Are Turning Us All Into Patients’, Allen & Unwin, 2005