How to mislead the public: a case study in apparent naivety


An article in today’s Daily Telegraph in the UK starts with the misleading statement that, “Up to half of men diagnosed with prostate cancer are being given ‘false hope’ by tests that are underestimating the severity of their disease, according to the authors of a new study.”

For starters, this isn’t what the study shows at all. But worse still, the article in The Daily Telegraph is going to give inappropriate angst to a whole lot of men who may be being managed entirely appropriately on active surveillance and other forms of expectant management.

Many other media outlets in the UK (including our friends at The Daily Mail) printed similarly inappropriate stories yesterday with very similar headlines and content, suggesting that someone distributed a misleading media release. However, none of the media provide a primary source for their stories.

The article by Shaw et al., published on line yesterday in the British Journal of Cancer, is entitled “Identification of pathologically insignificant prostate cancer is not accurate in unscreened men.” Let’s emphasize that: “Identification of pathologically insignificant prostate cancer is not accurate in unscreened men.” Pathologically insignificant prostate cancer and clinically insignificant prostate cancer aren’t necessarily the same things at all.

What Shaw et al. actually did was to publish data on a series of 848 patients who were all treated by radical prostatectomy between July 2007 and October 2011 at a single English tertiary care center. So for starters, not a single one of these patients was managed on active surveillance or any other form of expectant management.

The authors found that:

  • 415/848 patients had Gleason 3 + 3 = 6 disease on initial biopsy.
  • Of these 415 patients
    • 133/415 (32.0 percent) had extraprostatic extension at surgery.
    • 208/415 (50.2 percent) were upgraded after surgery.
    • 1/415 (0.2 percent) was found to have positive lymph nodes at surgery.
  • Only 206/848 patients (24 percent) met initial criteria for D’Amico low-risk prostate cancer.
  • Of these 206 patients,
    • 143/206 had more than two biopsy cores involved.
  • None of the “tools” evaluated by the authors has adequate discriminative power on its own to predict clinically insignificant tumor burden with certainty.

The authors conclude that, in this unscreened cohort of patients,

… tools designed to identify insignificant [prostate cancer] are inaccurate. Detection of a wider size range of prostate tumours in the unscreened may contribute to relative inaccuracy.

However, what is not discussed at all is the clinical relevance of any of this theoretical discussion.

Let’s start by being clear that no one has ever suggested that just because a patient meets D’Amico criteria for low-risk disease that he is necessarily a good candidate for any form or expectant management (active surveillance included). Furthermore, among men who are older and have multiple co-morbidities, expectant management of some type may well be an extremely good way to manage early stage prostate cancer, even when patients do not meet the D’Amico criteria for low-risk disease.

All that we know, when someone is characterized as meeting the D’Amico criteria for low-risk disease is that he may be a good candidate for expectant management. Such a patient needs careful work-up and re-evaluation before he is told that he actually is or is not a good potential candidate for active surveillance or any other form of expectant management.

Dr Shaw himself is quoted in The Daily Telegraph as saying that his study

… highlights the urgent need for better tests to define how aggressive a prostate cancer is from the outset, building on diagnostic tests like MRI (magnetic resonance imaging) scans, and new biopsy techniques which help to more accurately define the extent of the prostate cancer.

Du-uh!

The necessity for a thorough and early work-up of patients who are possible candidates for active surveillance and other forms of expectant management was discussed in detail just a few weeks ago by Klotz in a discussion on the Cure Panel Talk Show. As Klotz pointed out, through such a careful work-up, including things like multiparametric MRI scanning and re-biopsy of areas of the prostate that are known to be areas of high risk for occult prostate cancer, it is possible to identify the vast majority of men who are definitively not good candidates for expectant management.

What is more, it seems likely that, at most, only about 200 of the patients treated by Shaw et al. were ever even potential candidates for expectant management! Of course that leads one to ask just how many of the patients given a radical prostatectomy by Shaw and his colleagues were actually over-treated: 50, 100, 150?

Papers like this one by Shaw and his colleagues are jumped on by the media to spread inappropriate fear among patients and to feed an inappropriate perception among some clinicians that immediate surgery is the only possible way to manage any man with any amount of cancer found in his prostate. The Daily Telegraph and other media should be ashamed of this type of fear-mongering; Dr. Shaw and his colleagues need to become a tad wiser about what they say to the media; and it is very possible that the publishers of the British Journal of Cancer sent out a media release that could, at best, be described as “naive” (in the extreme).

 

8 Responses

  1. Thanks for consistently cuttting through the mustard.

  2. It is very rare today that the popular media convey complete information regarding any stories related to the scientific and medical community. It was only a few weeks ago that the Wall Street Journal and other outlets misreported an analysis publicized in the New England Journal of Medicine, where they were confusing watchful waiting with active surveillance. This is just another reason why this site is so important, to separate out the fact from the bull.

    Thanks

  3. Mike,

    This information is nothing new. Others have published similar data results when radical prostatectomies are performed in Gleason 6 patients. The bottom line is that the current tools available today are not consistently able to segregate potentially aggressive disease from a truly indolent form of the disease. Data from US patients where PSA is used more often might not be representative of other countries where men are diagnosed with more advanced disease and potentially more occult advanced disease.

    If the intent of the Shaw article is to misinform then why the intent of some medical experts that Gleason 6 represents an indolent form of disease? There is an inclination by some of them to even not referring it as cancer to reduce the rate of over-treatment. Isn’t that misinformation?

    It seems to me that the uncertainty of our current diagnostic tools are obvious and not fully capable to identify disease that can progress if given time while untreated.

  4. I add my thanks for your analysis.

    As you know from our offline discussion, Mike, the “NHS choices” article, sponsored by the NHS itself, hardly improves on the daily rags.

    Have you considered a letter to the Editor of The Daily Telegraph — with your byline it might just get published?! I did send in some comments to “NHS Choices”.

  5. Typical of the UK’s two worst newspapers.

  6. That interview and Q&A with Dr. Klotz about active surveillance on the Cure Panel Talk Show was superb! Thanks for your role in that Mike. I’m going to get the link distributed to our Us TOO chapter and try to get it on our state coalition site.

  7. Dear Ralph:

    I didn’t say that it was the “intent” of Dr Shaw and his colleagues to misinform anyone. What I said was that the way the data were presented by the media was highly misleading because it was being inappropriately implied that half the patients diagnosed with Gleason 6 disease were being mislead about their management.

    No one with even half a brain has ever argued that every patient with Gleason 6 disease isn’t ever going to need treatment of some type. The questions are: treatment for what, what type of treatment, and when?

    It is increasing clear that true Gleason 6 disease does not have the potential to metastasize. It is quite certainly the case that a proportion of men diagnosed with Gleason 6 disease will get upgraded (although it is still not clear what percentage of those men will benefit from treatment) — especially if an appropriate work-up isn’t conducted prior to a decision to manage them expectantly.

    However, it has certainly been argued by many surgeons (and it is still being argued by some) that any form of expectant management is inappropriate. This paper and the associated media coverage feed that argument.

    The bottom line is that every patient needs to understand his options and make decisions in consultation with a physician who presents the available data in an unbiased manner. Having an initial diagnosis of Gleason 6 disease is not a “black or white” issue as to whether treatment is or will become necessary. As you well know, that will depend on at least half a dozen other factors — starting with the age of the patient and the amount of cancer in his prostate (or outside it) and any associated symptomatology. Some men with even true Gleason 6 disease are going to need treatment for symptoms associated with the growth of their tumor — but even then they may not need a radical prostatectomy or radiation therapy or ADT. It may be possible and wise to just treat the symptoms.

    Other men with true Gleason 6 disease will indeed need a radical prostatectomy — because they are psychologically unable to live with the idea of having cancer at all.

    Further, no one I know of is arguing that we have the tools today to definitively discriminate between truly clinically insignificant and truly clinically significant disease. So it is unclear to me why Shaw et al. felt the need to make that point for the 250th time.

    You are completely correct in stating that data like these have been presented many times before (which is why I didn’t include all the references you provided). So why the media fuss about this paper anyway? For all I know, if and when Dr. Shaw spoke to the media, he stated categorically that this study did not in any way prove that expectant management was not appropriate for carefully selected patients — but it certainly doesn’t sound like it. However, whatever he said to them, the media chose to use an inaccurate headline and feature the idea that men electing expectant management were necessarily being misled. And since so many of the media stories used exactly the same phrases and statements, it is clear to me that someone sent out a misleading media release.

    “Tests” don’t give men “false hope”. Bad doctors give patients “false hope”. And bad media coverage gives men misleading information. Dr. Shaw and his colleagues were at least complicit in the bad media coverage, as was whoever decided to send out the media release.

  8. I suggest that it’s a predictable attempt of the Torygraph and the Daily Fail, to show how really bad the NHS is, so that the ConDem Coalition can have one more phoney excuse to complete its destruction by degradation followed by privatisation.

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