By Robert Bazell
Chief Science and Medical Correspondent
NBC News

Women who have received a “false positive” on a mammogram may have new cause for worry, according to a study released Thursday.

A false positive occurs when a radiologist detects an abnormality in a mammogram – that is, there is some apparent growth that is checked out, usually with a needle biopsy -- but it is determined there is no cancer. The research from the University of Copenhagen found that women who have been given additional testing because of a false positive run a 67 percent greater risk of a breast cancer diagnosis in the future.  Experts say the result from the records of 58,000 women in Denmark is not cause for alarm.  But it is a warning for those who have gotten a false positive to be more vigilant.

False positives may just be an artifact that appears on the mammogram, but they also include abnormally growing cells classified as atypia, papilloma or lobular carcinoma in situ. These are not cancer and they don’t require treatment, but women with these growths “have a 25 to 33 percent lifetime chance of developing breast cancer versus 11 percent in the general population,”according to Dr. David Dershaw, head of breast imaging at Memorial Sloan Kettering Cancer Center in New York.  So, any woman who has a false positive should consider a conversation with her doctor about whether she needs more frequent checkups or screening with higher resolution technology such as MRI.

There were further questions about mammograms in a large study released Monday, where researchers followed the records of almost 40,000 women in Norway.  Because that country phased in regular mammography from 1996 to 2005, the researchers were able to look at the effects before and after regular screening.  The study leaves no doubt that the screening is saving lives.  But it found that between 15 and 25 percent of the women diagnosed with breast cancer would have lived to die of some other cause and thus did not need treatment.

Such “overdiagnosis,” as the study authors including some the Harvard School of Public Health characterize it, is inevitable with any cancer screening test. Some cancers can kill.  Others never do.  But as Dershaw puts it “until it is possible to differentiate which are bad and which are not, all need to be treated.”

The extent and potential harm of overdiagnosis make up almost all of the arguments about cancer screening tests.  For some tests such as colonoscopies or pap tests the removal of abnormal growths that could become cancer subjects the patient to relatively little risk or discomfort.  The PSA screening test for prostate leads so many men to harsh treatments they often do not need that many question its usefulness.

Most experts believe the overdiagnosis from mammography – especially for women 50 and older— is well worth it for the lives saved.

But one of the reasons why there is such continuing debate about the screening test is that it is far from ideal.  Not only does it find cancers that will never be dangerous it can often miss ones that go on to be life threatening. 

Many medical and activists groups have pushed hard to get more women screened with mammography.  That is a noble goal.  But it is a mistake to think that is the solution to the great public health threat of breast cancer

Some of the most hopeful breast cancer research is a search for a blood test or other reliable method of detecting breast cancer early, especially the life threatening forms.  MRIs find more but also are so expensive and find so many false, that most doctors say they should be reserved for women at very high risk.

Neither study is an argument for women to avoid regular mammograms. Until scientists achieve the goal of finding a more reliable and cost effective test, it is the best breast cancer screening tool available.  

Robert Bazell is NBC's chief science and medical correspondent. Follow him on Facebook and on Twitter @RobertBazellNBC

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Recent use of the injectable contraceptive Depo-Provera for at least a year was associated with a doubling of young women’s breast cancer risk, a new study has found.

However, users’ breast cancer risk dropped to that of non-users within several months of stopping Depo-Provera injections, researchers report in the journal Cancer Research.

Depo-Provera, injected every three months, was approved as a contraceptive in the United States 20 years ago. Convenient, highly effective and relatively inexpensive, Depo-Provera is used by about 1.2 million U.S. women, or 3.2 percent of those who practice contraception, according to the latest data from the Guttmacher Institute, a research and education organization that focuses on reproductive health. 

The injectable birth control method is the only contraceptive in the United States that contains the same progestin, or synthetic hormone, as Prempro, the postmenopausal hormone therapy pill. A landmark government study called the Women’s Health Initiative found that Prempro, a combination of estrogen and progestin, increased women’s breast cancer risk by 24 percent, while Premarin, which contains only estrogen, did not increase risk.  

‘’Our hypothesis going into this study was that we did expect to see an increased risk of breast cancer associated with Depo-Provera,” says Dr. Christopher Li, a breast cancer epidemiologist at the Fred Hutchinson Cancer Research Center and lead author of the new study.

Data on the relationship between Depo-Provera and breast cancer risk are limited, the researchers write. Li and his coauthors say theirs is the first large-scale U.S. study specifically designed to evaluate the relationship. Results from similar studies conducted in other countries have been mixed, they write.

Li’s team recruited 1,028 women who’d been diagnosed with breast cancer and 919 women who had not. All the women were 20 to 44 years of age and lived in the Seattle area. About 3 percent had used Depo-Provera within the last five years.

Compared to women who had never used Depo-Provera, those who had received injections within the previous five years were 2.2 times more likely to have been diagnosed with breast cancer, the scientists found. Family history, obesity, age and pregnancy history didn’t seem to make a difference.

Age is the main risk factor for breast cancer, so while a doubling of risk might sound alarming, Li emphasizes that the actual number of breast cancer cases in women in their 20s and 30s is very low.

“Breast cancer among young women is still a rare disease,” he says. According to the National Cancer Institute, women in their 30s have a 1 in 233 chance of being diagnosed with the disease. By comparison, the odds of being diagnosed with breast cancer for women in their 60s is 1 in 29.

“However,” Li and his coauthors write, “there are numerous contraceptive options, and so further clarifying the benefits and risks associated with each option is important as women consider what choices might be best for them.”

Joan Campion, spokewoman of Pfizer, the maker of Depo-Provera, said, "As part of the Depo-Provera label, physicians are already advised on benefits and risks of Depo-Provera, including the risk of breast cancer. Pfizer currently believes that changes to benefits and risk profile are not warranted as a result of this observational study."

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By Anna Azvolinsky
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Ingesting higher levels of cadmium, a metal found in fertilizers, may be linked to an increased risk of breast cancer, a new study from Sweden suggests.

The results showed that postmenopausal women with a relatively high daily dietary cadmium intake had a 21 percent increased risk of breast cancer.

The major sources of cadmium in the diets of women in the study were foods that are generally healthy — whole grains and vegetables. These accounted for about 40 percent of the cadmium consumed.

The reason for the link may be that cadmium can cause the same effects in the body as the female hormone estrogen, the researchers said. Estrogen fuels the development of some breast cancers.

Whole grains and vegetables generally protect against cancer, and people should not avoid these foods because of this study, said study researcher Agneta Åkesson, associate professor at Karolinska Institutet in Sweden.

The study showed an association, not a cause-and-effect link, in one population of women, and further work is needed to confirm the findings.

"Though no single observational study can be considered conclusive, this very large, prospective study of [cadmium] exposure and post-menopausal breast cancer makes an important contribution to what is a fairly sparse literature considering this very important topic," said Michael Bloom, a professor at the School of Public Health at the University of Albany, who was not involved in the study.

Cause for concern?

"It has been known for some time that cadmium is toxic and, in certain forms, carcinogenic," said study researcher Bettina Julin, of the Karolinska Institute of Environmental Medicine.

In the study, the researchers collected data from more than 55,000 women in Sweden for 12 years. The women kept a daily log of everything they ate. The researchers estimated how much cadmium the women's consumed based on the country's data on the amount of cadmium in foods, and divided the women into three equally-sized groups based on their intake.

Over the course of the study, there were 2,112 breast cancer cases among the women: 677 in the women in the lowest cadmium intake group, and 744 in the women in the highest cadmium intake group. Because women's risk of breast cancer rises with age, the researchers took the women's ages into account when calculated the increased risk seen in the high intake group.

The researchers said they are concerned that cadmium is found in foods we consider healthy. The metal is well-absorbed by farmed plants, and fertilizers used to help grow our fruits, vegetables and grains contain cadmium.

The researchers noted that whole grains and vegetables, which were found to contain the most cadmium, have many beneficial nutrients — some that likely counteract the negative effects of the toxic metal.

And the data showed that women who ate the most whole-grain foods and vegetables, even when these foods contained cadmium, were less likely to develop the cancer than women who ingested high levels of cadmium through other types of food.

The highest risk of breast cancer was found among women who had a high cadmium intake, but ate few whole grains and vegetables.

Potatoes, root vegetables such as carrots, and cereal grains can accumulate cadmium from fertilizer and environmental deposits. Other types of food known to have a higher cadmium content include shellfish, organ meats and sunflower seeds.

Balancing act

"A major limitation of such a large-scale study is the exposure assessment," said Alfred Bernard, of the department of medicine at Catholic University of Louvain in Belgium. In other words, the researchers estimated cadmium intake, and that may not accurately reflect the actual amount consumed or the absorbed by the body.

Still, because of the high incidence of breast cancer, compared with other types of cancers among women, "even a modest increase in risk will stimulate a substantial public health concern," Bloom said.

Some researchers aware of the link of cadmium and cancer are taking reasonable precautions. "I have reduced my consumption of sunflower seeds considerably," Carolyn Gallagher, of the Department of Preventive Medicine at Stony Brook University in New York, told MyHealthNewsDaily. Sunflower seeds have a relatively high level of cadmium.

Getting enough iron may also reduce the body's uptake of dietary cadmium, which may help reduce risk, Gallagher said.

The findings are published today (March 15) in the journal Cancer Research.

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Some participants in Susan G. Komen for the Cure events, like this run in San Diego, have reconsidered their support in the wake of a controversy over Planned Parenthood funding this week.

Fierce controversy over a policy that cut -- then apparently restored -- funding for Planned Parenthood by the Susan G. Komen for the Cure breast-cancer charity has left some longtime supporters of both groups feeling whipsawed by the fallout.

Fans who’ve worn pink ribbons and jogged in Race for the Cure runs and those who’ve supported women’s reproductive health services had mixed reactions following news Friday that Komen had agreed to amend criteria that would have barred Planned Parenthood from future grants.

Some Komen supporters said the organization had alienated them forever by cutting funding in the first place based on perceived political pressure from anti-abortion groups.

“It’s difficult for me to want to continue to support Komen now,” said Peg Callaway, 63, a lawyer from Omak, Wash. “It makes me mistrust the organization.”

As the Associated Press first reported Tuesday, Komen had adopted criteria excluding Planned Parenthood from future grants for breast-cancer screening because it was under government investigation, citing a probe launched by a Florida congressman at the urging of anti-abortion groups.

The decision was made in December, but became public this week, igniting a firestorm of protest. By Friday, Komen appeared to back off the plan, saying it would fund existing Planned Parenthood grants, and that the agency would be eligible for future grants. Some critics said it wasn't clear how the decision actually would affect future grants.

Still, Callaway remained suspicious.

“They’ve done a lot of damage to themselves,” she said.

Others, however, said that Komen’s quick reversal made them want to give an agency another chance. Dina Lalli-Bender, 47, of Laurel Springs, N.J., said she participated last year in a Race for the Cure event in Philadelphia in memory of close friends and family members lost to breast cancer.

“I’ll continue to do the run now,” said Lalli-Bender, a senior manager at a trade show labor firm. “Now that they’ve changed their minds, maybe they’ve seen that people were outraged by it.”

But avid Komen supporters who had been cheered by what they saw as a strong stand against Planned Parenthood were dismayed that the agency appeared to back off.

“I was very disappointed to hear that the decision was reversed so quickly,” said Rita C. Hruschak, 69, a retired nurse from Webster, N.Y. “It was barely warming up the griddle. The hope for a positive change to some good morals was lost too soon.”

She pointed to Planned Parenthood’s huge base of support -- including $3 million and 10,000 Facebook fans raised during the three days of the controversy -- as evidence that the agency could fund breast cancer screenings on its own. Planned Parenthood previously had received about $700,000 a year from Komen.

“So you know, they don’t really need Komen’s help or support,” she said.

In an informal msnbc.com poll Thursday, more than 6,000 respondents considered whether the controversy would alter their donations to either group.

Some 73 percent of people of took the poll said it would increase their donations to Planned Parenthood, while about 17 percent said it would increase funding to Komen. Nine percent of respondents said they don’t donate to either group.

Only 1 percent said they’d continue donating to both.

Has the Komen decision, and then apparent reversal, changed how you feel about the organization? Tell us on Facebook.

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From the time a promising new cancer drug is discovered to when it is proven to work typically takes 10 to 15 years and can cost from $1 to $2 billion. Within the pharmaceutical and biotechnology industries this span of time is called the “valley of death,” a term that has both metaphorical and literal meaning.

The clinical trial known as ISPY-2 is an attempt to shorten this approval process for breast cancer drugs. It is run by the Foundation for the National Institutes of Health and supported in large part by the Safeway’s food chain’s charitable foundation. The trial is being conducted at 20 medical centers across the country.

Chemotherapy drugs (including hormone treatments) are normally used against cancer in one of various circumstances. One is for cancer that has spread after the initial surgery and radiation, a situation that doctors call “treatable but not curable” and want to avoid if at all possible. Another is to try to prevent recurrences in cancers that appear to have a significant risk for coming back.  If that prevention succeeds, the patient is cured. Usually doctors give this chemotherapy as so-called adjuvant treatment in the weeks and months following the initial surgery and radiation.

The key to ISPY-2 (all clinical trials these days are known by acronyms) is an approach known as neo-adjuvant chemotherapy. The patient gets the chemo-hormone combination before the surgery. Using MRI scans, the researchers can watch in real time to see if a drug combination is shrinking a tumor. Sometimes it shrinks so much that there is little to find when it comes time for the surgery. 

This procedure allows for quick comparison of an experimental drug combination with the standard care. In the future the researchers will be able to look for molecules in the tumors (so called bio-markers) that will help determine which combination will be the best. The hope is that the trial will more quickly identify drugs to help thousands of women. Most experts see this sort of “personalized medicine” playing a big role in the future.

But ISPY-2 requires a leap of faith. Does chemo before surgery do as much good as chemo afterward?  Absolutely, says Dr. Laura Esserman of the University of California, San Francisco, who heads the effort.

“The truth of the matter," she says, “is if you're going to die of breast cancer you're not going to die of the tumor that's in your breast. You're going to die because the tumor has spread outside the breast and those cells can take up residence someplace else in your body. The only way you're going to save that person is to make sure that you eradicate all of those cells wherever they may be and the sooner you start with the whole body treatment the better off you’re going to be.”

After a  mammogram, Dorothy Warren learned she had something called DCIS -- almost breast cancer, but not quite the same.

"You're gonna tell me I have cancer and I have stage zero, and it's not real invasive cancer?  I was not only fearful, but confused," Warren said.

Dr. Pamela Otto, a breast radiologist at the University of Texas, San Antonio, says DCIS consists of cancer cells that are inside the milk ducts.

Doctors cannot be sure if it will spread -- or if the patient needs to be treated with radiation or mastectomy.

Today's study, presented at a major breast cancer conference in San Antonio, finds that a genetic test called Oncotype Dx  can help with decisions about how to treat these cases. It gives a score, indicating how high the risk is.

Dr. Kathy Miller, a cancer expert at Indiana University School of Medicine, calls this "huge news" for women: “It allows us to make individualized treatment decisions.”

These results are part of a big movement to try to use genetic markers to tailor the care to each patient.

Experts say only about one-quarter of DCIS patients need radiation.

"Now we can look and say what is your specific risk?  Are you in the three-fourths who have a very low risk,” said Dr. William Wood, a cancer surgeon at Emory University School of Medicine.

This finding could give useful guidance for tens of thousands of women every year.

What should someone dying of cancer do when the last-ditch drug that they have relied upon is shown not to work? 

And what do insurance companies and government programs do about coverage when bad news arrives showing that the expensive life preserver to which many are clinging does no good -- and may actually accelerate a more miserable death? 

These are precisely the horrible dilemmas that many women dying of end-stage breast cancer face with the Food and Drug Administration’s finding that the drug Avastin does not work.

In 2008, the FDA allowed Avastin to be marketed as a treatment for incurable breast cancer. The approval came under a "compassionate access" program that allows very sick patients access to drugs before all the data that drug companies need to gather to show proof of efficacy has been collected.  All the data on Avastin is now in.  It does not show any real benefit to women in this desperate situation.

Still, many women with no other option will want to give Avastin a try. And they may be right in that the failure of a drug to show any benefit to a big number of women does not mean that no individual woman might benefit a tiny bit.  Still, the picture painted by the data is bleak, the drug costs about ten thousand dollars a month, and it is most likely just to make you sicker as you die.

Those now on Avastin should be allowed by their insurers to make the choice to stay on. The cost is large but it would be wrong to deny the drug to those who want to keep taking it even if the most likely result is that these women will provide the final sample of evidence that Avastin is a failure. But, for new patients not on the drug, the only fair option is to let them have access but not to pay for Avastin with government or private insurance money. 

The hope that Avastin might extend the lives of those dying from breast cancer is gone.  Those who still want to rely on the drug as they die should not be denied that last choice -- as poor as that choice may be. 

But there is no ethical argument in favor of paying for a very expensive drug that does not work for new patients, even when there is nothing else to offer.

Breast cancer drug revoked for 'life-threatening' risks

Kin Cheung / AP

By Rachel Rettner
MyHealthNewsDaily 

Even as few as three alcoholic beverages per week may increase a woman's risk of developing breast cancer, a new study finds.

Women in the study who drank three to six glasses of wine per week were 15 percent more likely than those who did not drink to develop breast cancer, researchers found in reviewing data taken over a 28-year period.

The study adds to the growing body of evidence of a link between alcohol consumption and an increased risk of breast cancer. Drinking moderate to high amounts of alcohol has previously been linked with breast cancer risk, but the effects of consuming low amounts of alcohol had been unclear. Alcohol may be increasing breast cancer risk by altering levels of the sex hormone estrogen, the researchers said.

Still, while the increased risk found in this study is real, it is quite small. Women will need to weigh this slight increase in breast cancer risk with the beneficial effects alcohol is known to have on heart heath, said Dr. Wendy Chen, of Brigham and Women's Hospital in Boston. Any woman's decision will likely factor in her risk of either disease, Chen said.

Chen noted that women who consumed fewer than three drinks per week had no increase in breast cancer risk.

"I don't think the take home message would be that women can't drink at all," Chen said.

Chen and colleagues examined information from 105,986 women who were followed from 1980 to 2008 as part of the Nurses Health Study. Women periodically answered questionnaires about their alcohol consumption and whether they had been diagnosed with breast cancer.

During the study period, 7,690 cases of invasive breast cancer were diagnosed.

The study found a rate of 333 cases of breast cancer per 100,000 women among those who drank three to six glasses of wine per week. There were 281 cases per 100,000 for women who drank no alcohol.

For those who consumed more than six glasses a week, the risk was higher. For women who consumed at least two drinks a day, the rate was 413 cases per 100,000 women — a 51 percent increase in breast cancer risk.

The study will be published tomorrow (Nov. 2) in the Journal of the American Medical Association.

It's not clear whether women could benefit from ceasing to drink alcohol by a certain age, wrote Dr. Steven Narod in an editorial accompanying the study. For instance, if alcohol exerted effects similar to hormone therapy (a treatment known to increase breast cancer risk in post-menopausal women), then women over 50 might benefit from cessation, said Narod, of the Women's College Research Institute in Toronto.

For some women, it seems the increase in risk of breast cancer may be substantial enough that cessation would be prudent. However, there are no data showing that giving up alcohol will reduce breast cancer risk, Narod said.

And it's possible that, for some, the benefit of drinking alcohol for the heart outweighs the risks of breast cancer, Narod said. Future research into alcohol's risks and benefits may provide women with more information to make a decision, Narod said.

Pass it on: Drinking three to six glasses of alcohol per week slightly increases breast cancer risk in women, a study suggests.

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Giuliana Rancic’s recent diagnosis of breast cancer at age 36 has generated a lot of emotional support for the E! host -- and some worries about the connection between fertility treatments and the disease.

During an interview with TODAY’s Ann Curry Monday about her efforts to have a baby, Rancic revealed that her cancer was discovered through a mammogram ordered up by her fertility specialist. Rancic, who has no family history of breast cancer, said she was dragged “kicking and screaming” to the breast screening after the specialist insisted on the mammogram before he would start a third cycle of in vitro fertilization, or IVF.

“He said, 'I don't care if you're 26 or 36, but I will not get you pregnant if possibly there's a small risk that you have cancer because the hormones will accelerate the cancer,'" Rancic told Curry Monday.

That advice may have helped save Rancic’s life, but it raised worries among some women. Could Rancic's breast cancer be connected in any way to the fertility treatment she had undergone?

 "No," said TODAY's Dr. Nancy Snyderman in a follow-up on the show Wednesday. The hormones used in both in vitro fertilization and birth control pills have been studied and "there's no known cause and effect," she told Curry. "What we do know is that women who are older usually ask for IVF because they're having a harder time getting pregnant -- and women who are older have a higher chance of getting breast cancer, so there is an age relation, but not a hormonal relation."

On Tuesday Rancic underwent a lumpectomy in both breasts and is now recovering.  Rancic was fortunate her doctor insisted on the screening. Mammograms are not a standard part of fertility treatment in patients her age, said Dr. Mark Perloe, medical director at Georgia Reproductive Specialists.

 “We certainly want people to have a full health evaluation before beginning fertility treatments,” Perloe added.  “But we wouldn’t recommend a mammogram unless there was a family history of breast cancer or a genetic risk.”

Breast cancer is unusual in women under 40 -- only 5 percent of all cases -- although the tumors can be faster-growing and harder to treat.

While many supporters on The Clicker Facebook page praised the benefits of mammograms, several commenters feared that "bad estrogen" or other hormones may have been connected to Rancic's diagnosis.

Hormones used in IVF cycles include estrogen, progesterone, follicle-stimulating hormone, and luteinizing hormone.

Despite the hormone paranoia, it's even possible that IVF might be protective.

“The evidence is that IVF has no effect or lowers incidence, said Adrian V. Lee, a professor of pharmacology and chemical biology and director of the Women’s Cancer Research Center at the University of Pittsburgh’s Magee-Womens  Research Institute. “The largest study in Sweden -- of 25,000 women who had IVF compared to 1.4 million without  -- showed a 25 percent reduction in breast cancer and a 40 percent reduction in cervical cancer in those who had IVF.”

Theoretically, Perloe said, if a woman had breast cancer, higher levels of estrogen and progesterone could stimulate the tumor to grow. But that would be true even if the woman got pregnant on her own because hormone levels rise as a pregnancy progresses.

"My concern is that this is going to cause a lot of people to be afraid," Perloe said. "My advice to anyone who has concerns is to speak to their doctor and learn to do breast self-exams -- and to check to see if anyone in their family had cancer before thet age of 40."

As for routine mammograms in infertile women aged 26 to 36, Perloe said, that would be a mistake. That's because mammograms come with some radiation exposure.

"So you have to balance the risk of exposure to radiation from testing against the likelihood that there might be something there," Perloe said.  

When women should begin mammogram screening is controversial. The U.S. Preventive Services Task Forces recommends breast cancer testing start at age 50, although the American Cancer Society advises yearly mammograms beginning at age 40 for women with an average risk.

So, women with infertility problems can relax, about their breast cancer risk at least. IVF treatments may not guarantee a baby, but they won't worsen your odds of developing cancer, doctors say.

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