Saturday, December 29, 2007

Black breast cancer is different

Those pesky genes again

African-American women diagnosed with breast cancer in their mid-30s or younger appear to be more likely than most other women to have a genetic predisposition for the disease, new research suggests. The study, published today in The Journal of the American Medical Association, is one of the first to examine the prevalence of mutations in the tumor suppressor gene BRCA1 by ethnic group in breast cancer patients with and without a family history of breast cancer. According to one estimate, nearly two out of three women who have the BRCA1 mutations are likely to develop breast cancer by age 70.

While African-American women as a group had a lower prevalence of BRCA1 mutations than most white and Hispanic women in the study, African-American women diagnosed with breast cancer before age 35 were roughly twice as likely to carry the mutations. If confirmed in larger studies, this finding could help explain why African-Americans tend to develop more aggressive and deadly breast cancers than other racial groups, says researcher Esther M. John, PhD, of the Northern California Cancer Center. "For whatever reason, African-American women are less likely to be tested [for BRCA mutations] than white women," John tells WebMD. "One message to clinicians might be that they should probably be tested more often."

The study included female breast cancer patients -- younger than age 65 at diagnosis -- enrolled in a California breast cancer registry between 1996 and 2005. Researchers confirmed a high prevalence of BRCA1 mutations among women of Ashkenazi Jewish ancestry, with 8.3% of these patients carrying the mutations compared to 3.5% of Hispanic women, 2.2% of non-Hispanic white women, 1.3% of African-American women, and 0.5% of Asian-American women.

Not surprisingly, BRCA1 mutations were more common in women with a family history of breast or ovarian cancer and less common in breast cancer patients diagnosed later in life. Roughly 17% of African-American patients diagnosed with breast cancer prior to age 35 carried a BRCA1 mutation, compared to 8.9% of Hispanic patients, 7.2% of non-white Hispanics without Ashkenazi Jewish ancestry, and 2.4% of Asian-American patients.

Larger studies are needed to confirm the findings, John says, because of the small number of young breast cancer patients enrolled in the study. Just 30 of the 341 African-American study participants were younger than 35, and five of them tested positive for BRCA1 mutations. John and colleagues conclude that a better understanding of the expression of BRCA mutations among different racial and ethnic groups will help doctors better identify women who should be screened.

In an accompanying editorial, Dezheng Huo, MD, PhD, and Olufunmilayo Olopade, MD, of the University of Chicago call the study by John and colleagues "a good starting point for narrowing the knowledge gap in characterizing the BRCA1 gene." Olopade tells WebMD that minority and other medically underserved women undergo genetic testing for BRCA mutations at a much lower rate than white women. She and Huo write that it is important "to design and evaluate interventions for improving genetic testing uptake in underserved populations, so that genetic testing can achieve full potential as a tool for effective cancer control and prevention."


A bad year to be fat in Britain

The year kicked off with the news that an overweight boy from North Tyneside could be taken from his mother by child protection officials. Her apparent crime: overfeeding her son. He was allowed to stay at home, but in the months to come various investigations - including one by the BBC - would uncover that obesity had been a factor in perhaps as many as two dozen child protection cases.

Some professionals said allowing a child to become obese had to be viewed as a form of neglect, given the potential health consequences. Others believed that to treat childhood obesity as a parental crime was foraying into unchartered - and potentially rather sinister - territory.

Other obesity-related headlines rolled in thick and fast. From fire chiefs considering charging to move large people from their homes to government equating obesity with climate change, fatness was never far away. "When we first started talking about obesity as a problem, it was very hard to be heard," says Dr Ian Campbell, medical director of the charity Weight Concern. "Now the pendulum has swung too far the other way - we hear nothing but. And the net result is that the kind of moralising the obese and overweight have always suffered has somehow become institutionalised."

One of the recent developments that particularly concerns the National Obesity Forum (NOF) is the move towards what has been described as "rationing" healthcare for the obese. According to one tally, there are at least eight NHS trusts which have introduced some form of restriction for non-urgent operations on the overweight. Such measures, which range from patients having to prove they have tried to lose weight to straightforward refusal to refer those above a certain BMI (body mass index), received something of an endorsement from then health secretary Patricia Hewitt earlier this year.

The fact is, doctors say, there are sound clinical reasons to delay treatment until patients lose weight. The operation is likely to be more successful, the recovery time shorter. But Dr Colin Waine, NOF chairman, believes that the obese are simply being used by hospitals as a convenient way to cut down on expenditure. "This is really about resources. You can't argue that denying a hip-and-knee operation to an obese person is in their interests, as it may well be the inability to walk about and exercise which is making their problems worse."

Recently the British Fertility Society has joined in, arguing that the obese should be barred from IVF as extra weight put the health and welfare of both mother and baby at risk. This, Dr Waine claims, is "discriminatory".

And the constant debate about the problems fat people pose can get very tiresome for those on the receiving end. "There's always been prejudice," says Vicki Swinden, founder of Fat Is The New Black. "But what's changed is that this now seems to be totally acceptable. It's perfectly legitimate now for a person standing in an airline queue to say: 'I'm not sitting next to that person, they're too fat.'" Fat Is The New Black argues that being fat does not necessarily mean you are not fit, or prone to ill health, and indeed this stance has been backed up by several studies. Most recently, a major US investigation found the overweight had no higher risk of dying of cancer or heart disease and overall lived longer than those of a "normal" weight.

Yet no-one seriously contends that obesity is not a problem - even if there is debate as to how great a risk it poses. But there is suggestion that perhaps we are harping on too much about it. "It's got to a stage now where it's actually hard to get any useful messages across because people have heard so much, often contradictory, information, that they just think: obesity blah blah blah," says Mrs Swinden.

The Health Secretary Alan Johnson recently said obesity was a problem "on the scale of climate change". Increasingly there are fears that we hear so much about the doom and gloom of global warming that we have started to switch off. "We don't want this to happen with obesity. We know what the problem is. We don't need more reports, more studies, more talking," says Dr Waine. "We just need to get with it now: the government, the food industry, the community and the individual - we need to get cracking."



Just some problems with the "Obesity" war:

1). It tries to impose behavior change on everybody -- when most of those targeted are not obese and hence have no reason to change their behaviour. It is a form of punishing the innocent and the guilty alike. (It is also typical of Leftist thinking: Scorning the individual and capable of dealing with large groups only).

2). The longevity research all leads to the conclusion that it is people of MIDDLING weight who live longest -- not slim people. So the "epidemic" of obesity is in fact largely an "epidemic" of living longer.

3). It is total calorie intake that makes you fat -- not where you get your calories. Policies that attack only the source of the calories (e.g. "junk food") without addressing total calorie intake are hence pissing into the wind. People involuntarily deprived of their preferred calorie intake from one source are highly likely to seek and find their calories elsewhere.

4). So-called junk food is perfectly nutritious. A big Mac meal comprises meat, bread, salad and potatoes -- which is a mainstream Western diet. If that is bad then we are all in big trouble.

5). Food warriors demonize salt and fat. But we need a daily salt intake to counter salt-loss through perspiration and the research shows that people on salt-restricted diets die SOONER. And Eskimos eat huge amounts of fat with no apparent ill-effects. And the average home-cooked roast dinner has LOTS of fat. Will we ban roast dinners?

6). The foods restricted are often no more calorific than those permitted -- such as milk and fruit-juice drinks.

7). Tendency to weight is mostly genetic and is therefore not readily susceptible to voluntary behaviour change.

8). And when are we going to ban cheese? Cheese is a concentrated calorie bomb and has lots of that wicked animal fat in it too. Wouldn't we all be better off without it? And what about butter and margarine? They are just about pure fat. Surely they should be treated as contraband in kids' lunchboxes! [/sarcasm].

9). And how odd it is that we never hear of the huge American study which showed that women who eat lots of veggies have an INCREASED risk of stomach cancer? So the official recommendation to eat five lots of veggies every day might just be creating lots of cancer for the future! It's as plausible (i.e. not very) as all the other dietary "wisdom" we read about fat etc.

10). And will "this generation of Western children be the first in history to lead shorter lives than their parents did"? This is another anti-fat scare that emanates from a much-cited editorial in a prominent medical journal that said so. Yet this editorial offered no statistical basis for its opinion -- an opinion that flies directly in the face of the available evidence.

Even statistical correlations far stronger than anything found in medical research may disappear if more data is used. A remarkable example from Sociology:
"The modern literature on hate crimes began with a remarkable 1933 book by Arthur Raper titled The Tragedy of Lynching. Raper assembled data on the number of lynchings each year in the South and on the price of an acre's yield of cotton. He calculated the correlation coefficient between the two series at -0.532. In other words, when the economy was doing well, the number of lynchings was lower.... In 2001, Donald Green, Laurence McFalls, and Jennifer Smith published a paper that demolished the alleged connection between economic conditions and lynchings in Raper's data. Raper had the misfortune of stopping his analysis in 1929. After the Great Depression hit, the price of cotton plummeted and economic conditions deteriorated, yet lynchings continued to fall. The correlation disappeared altogether when more years of data were added."
So we must be sure to base our conclusions on ALL the data. But in medical research, data selectivity and the "overlooking" of discordant research findings is epidemic.


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