Cancer Prevention

Too Much Health

There is a fascinating and timely report about Hormone Replacement Therapy in the Guardian today.

Survey after survey has linked hormone replacement therapy to cancer, strokes, blood clots and heart disease. Why, then, are so many women so relaxed about using it? And why do some doctors insist that the dangers are exaggerated? Sarah Boseley investigates

What it reveals is the continued attraction of HRT, more than a million women continue to take it in the UK, although for some of those women its pretty clear that taking HRT is not the optimum intervention.

What I find interesting about this is how compelling medical solutions can appear and how enduring they can be once the public first accepts them to be true. Once an idea like HRT has been promoted in the public realm, and once there is promotion of various sorts floating around, then its very difficult to get the idea our of the public imagination. None of us seem very attracted to the idea that actually medical intervention is bad for you.

I think many of us are afflicted by it. We go to doctors because we think they can help us. And they sometimes fob us off with placebos or what they think is more or less harmless sorts of drugs and interventions, such as HRT.

Its linked to my favourite piece of commentary of the year. Published on January 2nd, some of the best analysts in the business simply state,

For most Americans, the biggest health threat is not avian flu, West Nile or mad cow disease. It’s our health-care system. You might think this is because doctors make mistakes (we do make mistakes). But you can’t be a victim of medical error if you are not in the system. The larger threat posed by American medicine is that more and more of us are being drawn into the system not because of an epidemic of disease, but because of an epidemic of diagnoses.


Although this is a particularly American problem, UK patients are also afflicted. We demand and demand and demand in some situations where doing nothing might be the right thing to do.


The number of cancer deaths in the United States has dropped for the second year in a row, the American Cancer Society reported yesterday. The finding suggests that the small drop reported last year — the first in more than 70 years — was real, possibly the start of a continuing decrease and not merely a statistical fluke, researchers said.

The American Cancer Society's annual study of cancer mortality came out yesterday. And for the second year its great news.


The New York Times, though, has a tinge of pessimism in its second paragraph.
"Although the drop is notable, it still pales in comparison with the number of cancer deaths, 553,888 in 2004.....But it has taken enormous efforts and ingenuity to produce relatively small gains." And there is a graph attached to the piece which makes out that cancer mortality has rising from about 400,000 deaths in the US to about 550,000 since 1980.

Well. Although its right to be cautious, these figures should be cause for enormous cheer particularly because cancer mortality is not an isolated statistic. Since the 1980s, the rates of heart disease have declined by about 25 per cent since the mid 1980s. As the leading cause of death in the US is clattering down, people are dying of other things. And although cancer has been slow to catch up with cardiovascular treatments, it is catching up.

And more than anything this kind of statistic rebutts the widely held belief that cancer rates are increasing.

Link: Second Drop in Cancer Deaths Could Point to a Trend, Researchers Say - New York Times.


Cancer Research UK did this amazing piece of research, and they discovered that one in four people think that cancer has nothing to do with risk factors and is only down to fate.

It is amazing, after half a century of campaigning about smoking, and twenty five years about the sun, and a least a few decades about five fruit and veg a dag, how little the message gets through. In poorer areas, that number reaches almost half of the population believes its fate.

I think one of the reasons is the complete mumbo jumbo that is so often spoken about the disease. Yesterday a faith healer (admittedly quite a comic one) was on BBC2 explaining that cancer is all about emotions, and Sense About Science recently wrote about the rubbish that celebrities speak about science.

And this really affects people's lives.

It really is time to change how we think about cancer.


The sharp drop in breast cancer rates in the United States reported last week is astonishingly good news. It is the first major reduction in the incidence of a malignancy that strikes more than 200,000 American women every year — and kills some 40,000 annually.

This is extraordinary news. For the first time incidence in breast cancer is declining massively, by 7 per cent. It seems likely that is linked to the declining use of hormone replacement therapy. Which all goes to show that if we can understand the causes, then we can begin to tackle this disease.

Link: A big drop in breast cancer.

Red Meat and Breast Cancer

More bad news for red meat eaters. Not only is it bad for cancers of the gut, but it also seems to increase breast cancer risk.

Women who eat red meat every day are almost twice as likely to develop certain types of breast cancer, a long-term study published today has found.

Scientists who monitored 90,000 women for more than a decade found that those who ate a high meat diet were much more prone to developing the hormonally reactive breast cancers, which account for more than half of all breast cancers.

The scientists suggest that synthetic hormones used in meat production could be behind the trend.

The message is getting clearer and clearer.

Original Article.


My Dad always had a low PSA score. It meant doctors never thought he had a life threatening illness. At last there seems to be some hope that the PSA test is being refined.

The hoopla about the PSA test has been going on for more than a decade. At first it seemed almost like a panacea - men would be tested, cancer identified and eradicated - all would be good. But in the years since its introduction the PSA test has revealed many more men who have some kind of precursor to cancer which was not about to inevitably lead to death or illness. With so many so called ‘false-positives’ there has been much debate about whether the risks of the test were greater than the benefits of it. As a relatively young man, I’m only 39, its clear that the risks for me are much worse than the benefits. Even though something like twenty per cent of my age group probably already had some kind of precursor to the cancer – though many of these precursors wouldn’t hurt my life.

At last, though, the debate is moving on.

This month’s Journal of the National Cancer Institute has an interesting article about PSA. Rather than just trying to work out an absolute level, it comes to the conclusion that watching the pattern of the PSA is what is perhaps more important.

"In summary, when compared with a single PSA level threshold, the rate at which PSA levels reach a threshold value (PSA velocity) may provide useful information for identifying men who need further evaluation and/or closer surveillance for the presence of life-threatening prostate cancer."

My Dad had a pile of PSA tests. They all came up with numbers less than the supposed threshold of 4.0 ng/mL -whatever that means. Because it was below the threshold nobody thought it was important. But in the end he died.

The final conclusion of this paper, gives some hope that patients like Dad would not be overlooked in the future.

"When PSA levels are below 4.0 ng/mL, even small rises in PSA levels should prompt the consideration of the presence of a biologically important prostate cancer."

There is more discussion in the same journal here or in the New York Times here.

A Lung Cancer Breakthrough? - annual CT scanning

My contention is that it is rare to see in the newspapers a proper cautious approach to the dilemmas of prevention. Truth is, that the balancing of risks and benefits doesn't make that great storytelling, its too equivocal, and its too cautious for great journalism. But these careful judgements are the truth. I talk about one such story in a latter chapter in my book.

But here is a rare example. The good old New York Times in an editorial about a new lung cancer study.

Some cancer experts and advocates for lung cancer patients are hailing the dawn of a new era in which lung cancer will move from a disease that is usually fatal to one that is usually curable. So why do many experts have misgivings about recommending widespread CT scan screening?

For once it seems that the newspaper is offering the proper analyis, whilst the New England Journal of Medicine is offering a much less rigorous view.

Conclusions Annual spiral CT screening can detect lung cancer that is curable.


Today there is much hoopla about a new report from the nordic cochrane collaboration. The Press Association tells us that "thousands of women in England could be undergoing unnecessary and potentially devastating treatment for suspected breast cancer".

The Today Programme says that "new research says that breast cancer screening might be doing more harm than good."

The Telegraph that "Screening for breast cancer 'may harm women'"

Because the Cochrane collaboration is one of the most authorative in the world its worth taking it seriously. And yet if you actually read the paper itself its not the big news that everybody is going on about. In fact, the evidence is very similar to much that has been around for at least a decade. There is a chapter in my book which outlines a political scandal around similar figures in 1997.

And even though its not new, the paper itself seems to be much more tentative than the headlines.

Screening likely reduces breast cancer mortality. Based on all trials, the reduction is 20%, but as the effect is lower in the highest quality trials, a more reasonable estimate is a 15% relative risk reduction. Based on the risk level of women in these trials, the absolute risk reduction was 0.05%. Screening also leads to overdiagnosis and overtreatment, with an estimated 30% increase, or an absolute risk increase of 0.5%. This means that for every 2000 women invited for screening throughout 10 years, one will have her life prolonged. In addition, 10 healthy women, who would not have been diagnosed if there had not been screening, will be diagnosed as breast cancer patients and will be treated unnecessarily. It is thus not clear whether screening does more good than harm. Women invited to screening should be fully informed of both benefits and harms.

Its interesting that none of the media outlets link to the paper itself despite it being on public access.

Amidst the panic that goes on around a story like this, the key message that women should be allowed to make a real informed decision always seems to get lost. Surely its down to the patients, not the bureaucrats to make choices like this.

A vaccine, at last

Late in September 1970, many in the US cancer establishment were promising that a vaccine for cancer was imminent. They thought they had found virus particles in a whole variety of cancers. They thought that cancer would succumb to human endeavour just as Polio had a decade or so before.

In the end, cancer turned out to be a more intractable problem. Yet there was one cancer were a virus was pretty clearly the cause. That was cervival cancer.

In the 36 years since the virus cancer fad of the early 1970s, much has been done. And finally last week, the US FDA announced that it had licensed a vaccine for cervical cancer. What a result?


Our strange ideas about drugs

So at last the National Centre for Clinical Excellence has recommended that a new class of breast cancer drugs be allowed on the NHS. This news has taken a long time in coming. There has been some clinical trials that have shown the benefits of these newer and more expensive drugs for years.

What I find interesting is how aromatase inhibitors have been treated differently to Herceptin. The latter was hailed as a wonder drug. Tens of patients have been campaigning for their 'life-saving' drug. There has been a massive media campaign.

Yet arguably, aromotase inhibitors will save many more lives. The Daily Mail said they'd save 1000 lives a year in the UK. Of course, unlike Herceptin they are not based on the wonders of genetic manipulation. And they are only an improvement of an existing sort of drug - Tamoxifen has been working in a roughly similar way for twenty years. And as a consequence, they have sort of given a lower priority.

Its little wonder that patients find it so difficult to navigate the treatment choices - when the coverage in the newspapers is so lopsided.

Half of All Cancers are Preventable

This is interesting. The American Cancer Society says that so many cancers are preventable. Never mind the advances in treatments (or the scares about pesticides) - if only we followed a few simple things.

At least half of all cancer deaths could be avoided if we only did what we know works to prevent the disease. That's the conclusion of the 2006 edition of Cancer Prevention and Early Detection Facts & Figures, a yearly American Cancer Society report.

Cutting out tobacco, making use of cancer screening tests, reducing levels of obesity and overweight, and improving nutrition and physical activity could go a long way to lowering the number of cancer deaths in the United States, the report says.


Fat or Fiction

H Gilbert Welch and his colleagues describe wonderfully the problems of assessing the effects of dietary fat in The Washington Post

"The best data to date suggesting the potential for diet -- or any lifestyle alterations -- to affect cancer risk is limited. The single notable exception is smoking: There is no doubt that not smoking dramatically lowers cancer risk.

The effect of diet on cancer is likely to be small for most people because diet is so heterogeneous and the effect of any given food may depend on its interaction with other foods. And the smaller the effect, the harder it is to demonstrate statistically. So it is really not surprising that results of research about diet and cancer flip-flop. Low-fat diets probably do lower the risk of breast cancer -- but the effect on risk is small -- particularly for women with no prior history of the disease. Changing diet to reduce breast cancer -- or any other cancer -- is a personal decision, not an imperative."

Its very counter-intuitive. All the five-a-day campaigning is partly premised on the idea that better diet will reduce cancer risk. Yet the evidence about dietary fat is not quite there.

The trouble is that there is a gulf between what we know for certain and what we might presume. That said, few doctors would advise their patients anything other than switching to healthier diets for the prevention of a range of other diseases as well as cancer.