Revised Guidelines Say Most Women Can Begin Mammograms At Age 50

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According to the Atlantic's John Crewdson, the only American reporter at the Stockholm news conference in 2002, on The Lancet publication of the Swedish meta-analysis, analyzing and updating the half-dozen Swedish mammography studies that told us nearly all of what we knew about the value of mammography, last month, Dr. Otis Brawley, the cancer society's chief medical officer, was quoted in the New York Time admitting "that American medicine has overpromised when it comes to screening. The advantages to screening have been exaggerated."

Crewdson wasn't surprised by Brawley's statement, since he had expressed the same view to him when they met at a cancer symposium in Milan in 2003.

Following the task force report's release, however, Brawley appeared to change direction, telling the Times that the cancer society had concluded that the benefits of annual mammograms beginning at 40 "outweighed the risks" and that the ACS was sticking by its earlier advice. One of Brawley's colleagues said, "He's trying to save his job. He was broiled at home for the interview in which he said that the medical establishment was 'overselling' screening."

Dr. Donald Berry, head of biostatistics at the M.D. Anderson Cancer Center, points out that if the Swedish update is read carefully, the benefit for women 40-50 is really only 9 percent, which is not statistically significant, meaning it could represent the play of chance and not a real advantage. What Brawley failed to mention is that the numbers the news media are flinging around are the relative benefit. Utterly obscured is the number that really matters, the absolute benefit.

http://www.theatlantic.com/doc/200911u/mammograms

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The news about mammograms is not brand new information based on one study that just came out. The recommendations that the Preventive Services Task Force (PSTF) released is based on research that experts have known about for some time.

Dr. Herman Kattlove, a retired medical oncologist did research on mammograms in the early 1990's. For seven years, until his retirement in 2006, Kattlove had served as a medical editor for the American Cancer Society where he had helped develop much of the information about specific cancers that is posted on the society's website.

On his own personal cancer blog, Kattlove wrote, “Many years ago, the National Cancer Institute (NCI) tried to convince us all to not screen women younger than 50 and were given such a tongue lashing by Congress that they went home, licking their wounds, and withdrew their recommendation.”

Of course, Congress should not have become involved in telling the NCI what information it should make available to the public. Few Congressmen are either M.D.s or scientists trained to analyze and critique medical research. But this illustrates just how politically charged the question of diagnostic testing has become, especially when companies like GE that are making large profits on the sale of diagnostic testing equipment, and their lobbyists are helping to finance Congressional campaigns.

For decades doctors have urged patients to undergo mammograms because they sincerely believed that mammograms saved many lives. They, too, were not receiving all of the information they needed about the risks. Powerful forces stood in the way of widespread dissemination while millions of dollars were poured into the Mammogram campaign.

Kattlove goes on to say, “Likewise, the American Cancer Society also avoids looking clearly at the data and continues to recommend screening for younger women. And the morning’s paper carried lots of outrage from breast cancer specialists and other docs who are committed to screening younger women.

Some of the reasons for this are political and financial. The ACS doesn’t want to enrage its donor base, Congress didn’t want to upset constituents and breast cancer specialists have faith in the procedure. I’m sure all the pink breast cancer organizations are also organizing their protest.

Why this emotion and outrage? I think because we feel helpless when we see women die of breast cancer, sometimes while still young. Indeed, deaths in these young women hit us hard. So we want to do something and our only tool is mammography.

“But mammography is not the answer for these women.” As Kattlove points out in his post, when young women die of breast cancer they are usually killed by very fast-growing aggressive cancers that grow too quickly to be caught by early detection. The tumors crop up, and spread in between annual mammograms. Kattlove continues: “The unfortunate side effect of this delusion [that screening and early detection is the answer] is that we avoid the hard choices like healthy life styles and avoiding cancer-causing drugs such as hormone-replacement treatment.

I would add that while I applaud the PSTF for bringing this research to our attention, I wish that they had done this two or three years ago. From a political point of view, the timing is unfortunate because inevitably, those who oppose health care reform will exploit this report to suggest that, under reform, the Government will use “comparative effectiveness research” to deny necessary care—and as a result patients will die.

In fact, health care reformers, the government and Medicare understand that, after thirty years of telling women that they must have annual mammograms, we cannot turn on a dime and expect them to suddenly absorb the information that for most average-risk women under 50, mammograms pose more risks than benefits.

No one is going to stop covering mammograms. But responsible physicians will begin giving patients more information about what the medical research shows, including the fact that for most women, the danger of undergoing unnecessary radiation, or an unneeded mastectomy or lumpectomy, far exceeds the likelihood that a mammogram will save their lives.

Moreover, it is important to remember that the “comparative effectiveness information” that the government plans to generate will serve to create guidelines—not “rules”—for doctors. In the U.K., doctors use such guidelines about 88 percent of the time, which seems appropriate, giving how much variation there can be in individual cases.

Finally, under reform it is extremely unlikely that insurers (including the public plan) will stop covering treatments and tests (including PSA tests), that have been in use for a long time. More likely, they will lift co-pays and lower reimbursements for procedures that are less effective, while lowering co-pays and lifting reimbursements for procedures that the medical evidence shows are more effective.

In this case, unfortunately, we don’t yet have a good alternative to mammograms, a further reason why insurers will not suddenly stop covering the tests.

http://kattlovecancerblog.blogspot.c...-it-right.html

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The other side of the coin is radiation risk imposed by mammography. It is not simply of negligible value in younger women, but may have a net harm effect, if women who have mammograms at age 40 start having higher rates of cancer in irradiated breasts 25 or 35 years later.

The recommendation not to begin mammography until age 50 has to do with medical issues, more than cost effectiveness issues. Mammography is not harmless. You are subjecting women to annual doses of ionizing radiation to the breasts, with some unavoidable scatter to chest wall and lungs. We do not know how many women who are irradiated by mammography in their 40s will develop radiation-induced breast cancer (or even lung cancer) in their 60s, 70s, and 80s.

The other problem is that women in their 40s tend to have very dense breasts, making it more difficult to get an accurate exam. These women often are called back for additional views, giving them even more radiation. There are more false positives, leading to breast biopsies and sometimes unnecessary lumpectomies, in cases where the biopsies are technically suboptimal.

In contrast, in older women, their breasts are less dense, making the examination more accurate, with fewer false positives, and there are fewer years of remaining life to develop a radiation-induced malignancy.

The fact is that we have no truly long term follow up studies to determine very long term risks of carcinogenesis from radiation exposure in mammography.

1. J Radiol Prot. 2009 Jun;29(2A):A123-32. Epub 2009 May 19.

Mammography-oncogenecity at low doses.

Heyes GJ, Mill AJ, Charles MW.

Department of Medical Physics, University Hospital Birmingham NHS Foundation Trust, Birmingham B15 2TH, UK.

Controversy exists regarding the biological effectiveness of low energy x-rays used for mammography breast screening. Recent radiobiology studies have provided compelling evidence that these low energy x-rays may be 4.42 +/- 2.02 times more effective in causing mutational damage than higher energy x-rays.

The risk/benefit analysis, however, implies the need for caution for women screened under the age of 50, and particularly for those with a family history (and therefore a likely genetic susceptibility) of breast cancer. In vitro radiobiological data are generally acquired at high doses, and there are different extrapolation mechanisms to the low doses seen clinically. Recent low dose in vitro data have indicated a potential suppressive effect at very low dose rates and doses. Whilst mammography is a low dose exposure, it is not a low dose rate examination, and protraction of dose should not be confused with fractionation. Although there is potential for a suppressive effect at low doses, recent epidemiological data, and several international radiation riskassessments, continue to promote the linear no-threshold (LNT) model.

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The Washington Post addressed the mammogram recommendations by asking some questions to Kay Dickersin, director of the U.S. Cochrane Center and the Center for Clinical Trials at the John Hopkins Bloomberg School of Public Health (and a breast cancer survivor).

http://www.washingtonpost.com/wp-dyn...301801_pf.html

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The New York Times reports a paper in The Journal of the American Medical Association noted that data from more than two decades of screening for breast and prostate cancer call that view into question.

Besides finding tumors that would be lethal if left untreated, screening appears to be finding many small tumors that would not be a problem if they were left alone, undiscovered by screening. They were destined to stop growing on their own or shrink, or even, at least in the case of some breast cancers, disappear.

http://www.nytimes.com/2009/10/27/he...canc.html?_r=1

When women in four Norwegian countries began regular mammography every two years, breast cancer rates increased significantly, and this suggests that the mammography may have be detecting cancers that might have spontaneously regressed, according to an article released on November 24, 2008 in the Archives of Internal Medicine, one of the JAMA/Archives journals.

The start of regular screening through mammography in Europe was associated in increased incidence of breast cancer -- this is a relatively normal consequence of any new screening program. However, the authors note, "if all of these newly detected cancers were destined to progress and become clinically evident as women age, a fall in incidence among older women should soon follow." They continue, noting that this has not occurred: "The fact that this decrease is not evident raises the question: What is the natural history of these additional screen-detected cancers?"

To investigate the etiology of these newly identified cancers, Per-Henrik Zahl, M.D., Ph.D., of the Norwegian Institute of Public Health, Oslo, and colleagues observed breast cancer rates in women who were invited to participate in three rounds of screening mammograms between 1996 and 2001 in the Norwegian Breast Cancer Screening Program. A total of 119,472 women between the ages of 50 and 64 participated.

The rates in these women were compared to a control group in the same age range in 1992 who would have been invited for screening, if the program had existed in that year. National registries were used to track cancer rates. At the end of six years, these control women were invited to participate in a one-time screen for cancer prevalence.

Breast cancer rates were higher in the screened population than in the control group -- this was expected, as they were being checked more regularly. However, when the control group was screened, the total number of cancer diagnoses in the control population was lower than those in the screened group. "Even after prevalence screening in controls, however, the cumulative incidence of invasive breast cancer remained 22 percent higher in the screened group," write the authors.Over the course of the six years, 1,909 of the screened women in every 100,000 had breast cancer. In contrast, 1,564 of every 100,000 women in the control group had breast cancer. This was also true for every stratified age.

The authors give a potential explanation for these absent cancers: "Because the cumulative incidence among controls never reached that of the screened group, it appears that some breast cancers detected by repeated mammographic screening would not persist to be detectable by a single mammogram at the end of six years," they say. "This raises the possibility that the natural course of some screen-detected invasive breast cancers is to spontaneously regress."

They continue: "Although many clinicians may be skeptical of the idea, the excess incidence associated with repeated mammography demands that spontaneous regression be considered carefully." They add that this is not an unlikely scenario: "Spontaneous regression of invasive breast cancer has been reported, with a recent literature review identifying 32 reported cases. This is a relatively small number given such a common disease. However, as some observers have pointed out, the fact that documented observations are rare does not mean that regression rarely occurs. It may instead reflect the fact that these cancers are rarely allowed to follow their natural course."

Their findings cannot make a statement about mammograms' ability to prevent breast cancer deaths, they say. "Instead, our findings simply provide new insight on what is arguably the major harm associated with mammographic screening, namely, the detection and treatment of cancers that would otherwise regress."

Robert M. Kaplan, Ph.D., of the University of California, Los Angeles, and Franz Porzsolt, M.D., Ph.D., of Clincal Economics University of Ulm, Germany, contributed an accompanying editorial that notes that lack of knowledge which still persists about the natural history of breast cancer. "Despite the appeal of early detection of breast cancer, uncertainty about the value of mammography continues," they write. "In this issue of the Archives, Zahl et al use a clever study design in an attempt to estimate the value of screening."

"Perhaps the most important concern raised by the study by Zahl et al is that it highlights how surprisingly little we know about what happens to untreated patients with breast cancer," they continue. "In addition to not knowing the natural history of breast cancer for younger women, we also know very little about the natural history for older women. We know from autopsy studies that a significant number of women die without knowing that they had breast cancer (including ductal carcinoma in situ). The observation of a historical trend toward improved survival does not necessarily support the benefit of treatment."

"If the spontaneous remission hypothesis is credible, it should cause a major re-evaluation in the approach to breast cancer research and treatment. Certainly it is worthy of further evaluation," they finally conclude.

The Natural History of Invasive Breast Cancers Detected by Screening Mammography
Per-Henrik Zahl, MD, PhD; Jan Mæhlen, MD, PhD; H. Gilbert Welch, MD, MPH Arch Intern Med. 2008;168(21):2311-2316.

The Natural History of Breast Cancer
Robert M. Kaplan, PhD; Franz Porzsolt, MD, PhD Arch Intern Med. 2008;168(21):2302-2303. Dr. Robert M. Kaplan, chairman of the department of health services at the School of Public Health at the University of California, Los Angeles, who with his colleague, Dr. Franz Porzsolt, an oncologist at the University of Ulm, wrote an editorial that accompanied the study, were persuaded by the analysis, and feel the implications are potentially enormous.

Dr. Barnett Kramer, director of the Office of Disease Prevention at the National Institutes of Health, had a similar reaction. People who are familiar with the broad range of behaviors of a variety of cancer, know spontaneous regression is possible, but what is shocking is that it can occur so frequently.

And Donald A. Berry, chairman of the department of biostatistics at M. D. Anderson Cancer Center said the study increased his worries about screening tests that find cancers earlier and earlier. Unless there is some understanding of the natural history of cancers that are found, the result can easily be more and more treatment of cancers that would not cause harm if left untreated.

Dr. Berry felt that it's possible that we all have cells that are cancerous and that grow a bit before being dumped by the body. Screening tests may pick up minute tumors that would not progress and might even go away if left alone (pseudodisease). Patients will be alarmed and exposed, perhaps needlessly, to the risks of chemotherapy, surgery and radiation.

Spontaneous remissions in cancer suggests that the body can heal itself. It seems like most apparently occur in just a few types of malignancies: malignant melanoma, renal cell cancer, low-grade non-Hodgkin's lymphoma, chronic lymphocytic leukaemia and neuroblastoma in children. However, spontaneous remissions do occur in vastly different other types of cancers.

The very existence of spontaneous remissions represents a threat to some in the cancer industry. But such anomalies can pave the way to a better understanding of the causes of cancer which can then lead to rational therapies. Historical observations of spontaneous remissions of breast cancer after the onset of menopause lead to approaches of hormonal treatment which is a mainstay of adjuvant and palliative therapy in breast cancer.

Regardless, spontaneous remissions represent an important clue as to how the body can defend itself against cancer. Researchers should think "outside the box" at this important phenomenon rather than see it as a threat to their conventional thinking and appreciate the insight it may provide to rational approaches to cancer treatment.

For some common cancers, it is not clear that early detection and treatment actually prolong patients' lives. Early detection may just mean patients spend a longer time knowing they have cancer, and yet die at the same time they would have died anyway if the tumor had been diagnosed later. A decision to forgo cancer screening can be a reasonable option.

Literature Citation: Arch Intern Med. 2008;168(21):2300, 2302-2303, 2311-2316.