Thursday, 28 July 2011

The BBC stands by its junk journalism

Seven days after sending an e-mail to the BBC about its story which falsely claimed that obesity, drinking and smoking are the three biggest risk factors for breast cancer, I received a short and anonymous reply.

The original BBC story stated:

Obesity 'leading driver' of breast cancer

Obesity is the biggest driving force behind the most common form of breast cancer in older women, say researchers.

Alcohol and then cigarettes are the next largest culprits, according to Cancer Research UK.

This is arrant nonsense for several reasons, as I said in my e-mail to the Beeb (see here for the details). In summary, there is not a scientist in the galaxy who believes that obesity and drinking are the main "drivers" of breast cancer and only a handful of certifiable anti-smoking maniacs like Stanton Glantz believe that smoking is a risk factor for breast cancer AT ALL.

The BBC's reply:

Dear Chris

Many thanks for getting in touch and raising your concerns.

You are correct that it is important to stress that the findings mean that obesity affects the levels of sex hormones. The article does this. We were mindful of this and discussed this point and the wording with cancer research uk before publication of the article. We explain that it applies only to hormone sensitive breast cancer in postmenopausal women and that the link suggests obesity drives up hormone levels.

Thanks again for contacting us. We value your feedback.

Kind regards

Since this ignores every point I raised in my earlier e-mail, I replied:

Sir/Madam,

I don't take issue with the bulk of the story in question, which reflects the study accurately in some respects. The main problem is the headline and the first two paragraphs, ie:

Obesity 'leading driver' of breast cancer

Obesity is the biggest driving force behind the most common form of breast cancer in older women, say researchers.

Alcohol and then cigarettes are the next largest culprits, according to Cancer Research UK.

Every word of this is demonstrably untrue. It is not a matter of interpretation or wording. Obesity is NOT the biggest driver of breast cancer - as with all cancers, age is the biggest driving force. Between the age of 29 and 69, a woman's odds of developing breast cancer increases from 1 in 2000 to 1 in 13. As Cancer Research UK's website says: "The strongest risk factor for breast cancer (after gender) is age"

After that, there is reproductive history. Childless women have twice the risk as women with large families (who breast-fed).

Family history of the disease also doubled the risk.

These are the true driving forces of breast cancer. Way down the list is overweight and obesity, with a 10-30% increase in breast cancer risk. Again, from CRUK: "Compared to lean (BMI 22.5-24.9) women, overweight post-menopausal women have a 10-20% increased risk of breast cancer, and obese post-menopausal women a 30% increase in risk."

Alcohol is also a risk factor, varying on consumption, but generally is considered to form a 10-50% increase in risk. (eg. http://aje.oxfordjournals.org/content/165/6/667).

Smoking is not generally considered a risk for breast cancer AT ALL, despite efforts by the BBC and the Daily Mail to tell the public otherwise. To claim that it is the third biggest driver of the disease is ignorant and inexcusable.

Sex hormones are undoubtedly a risk factor, and a major one. The study you reported on shows that obesity is a risk factor for higher sex hormones and that drinking and smoking may be "moderate" risk factors for higher sex hormones. The crucial points - which I hoped I explained in the previous e-mail, but perhaps not - is that (a) the authors of the study NEVER claimed that obesity, drinking and smoking are the main risk factors for higher sex hormones, let alone breast cancer, and (b) even if these 3 factors were the main risk factors for higher sex hormones, it does not follow that they are the main risk factors - or the 'leading drivers' - for breast cancer itself. Indeed, we know with as much certainty as is possible to have in science that they are NOT.

Your article did not "stress" that obesity affects sex hormones. On the contrary, it stressed, quite wrongly, in the headline and opening sentences that obesity is "the biggest driving force behind the most common form of breast cancer in older women". This is untrue. It then stressed that drinking and smoking were the next biggest drivers of breast cancer. This is untrue. You say that: "This latest work, published in the British Journal of Cancer, suggests obesity should go at the top of this list [of risk factors for breast cancer]". This is untrue. The author of the study said, in the press release you were doubtless sent:

“Our study shows that changes in hormone levels might explain the association of established risk factors such as obesity with breast cancer risk. Other studies have found that weight and alcohol can affect hormone levels and this research confirms and adds to these findings and provides more information about how breast cancer develops.”

Nothing in the CRUK press release or the study itself in any way supports the premise of your article. Are you prepared to stand by your claim that obesity, drinking and smoking are the "biggest driving forces" for breast cancer? If not, the article should be changed. It is too late to avoid misleading the bulk of its readers, but it would at least be an acknowledgement that the BBC knows when it has made a mistake.

Regards,

Chris Snowdon

Their reply...

Thank you for your comments, which have been noted.

BBC News website

Translation: 'Piss off and leave us to report Cancer Research UK press releases in anyway we see fit.' Needless to say, the article in question remains unchanged, so any woman who has recently been diagnosed with breast cancer can read it and blame herself for the disease.

I should say that my interest in pursuing this—as I will continue to do—is not because it is the worst example of BBC reporting I have ever seen. Far from it. It is because it is an open and shut case. Their reporting of this particular story is wrong in essence and in fact. To publish such garbage in the first place is lamentable, if forgivable, but to stand by it is appalling.