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Are Dense-Breast, Right-to-Know Laws Helpful?

Are Dense-Breast, Right-to-Know Laws Helpful?

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Doctor examines digital mammogram, pointing to a possible cancer. Credit: National Cancer Institute

In a victory for the dense-breast patient movement, Governor Jerry Brown (D-CA) signed legislation last week requiring that doctors who discover that women have dense breasts on mammography must inform women that:

  • dense breasts are a risk factor for breast cancer;
  • mammography sees cancer less well in dense breasts than in normal breasts; and
  • women may benefit from additional breast cancer screening.

The California law goes into effect on April 1, 2013. It follows four states (Connecticut, Texas, Virginia, and New York) with similar statutes. All have enjoyed solid bipartisan support. Rarely do naysayers or skeptics speak up.

Young women who are leading the charge often bring lawmakers the story of a young constituent, diagnosed with a very aggressive, lethal cancer that was not shown on film-screen mammography. The Are You Dense? patient advocacy group engages patients on Facebook, where women share their experiences with breast cancer and organize events. Individual radiologists work with the advocacy groups, but many radiology groups and breast surgeons do not endorse these laws.

A Closer Look at Breast Cancer Data

Living in an age when information is viewed as an entitlement, knowledge, and power, many physicians find it hard to argue against a patient’s right to know. Can sharing information be a mistake? Some epidemiologists think so. Otis W. Brawley, MD, FACP, Chief Medical & Scientific Officer, American Cancer Society, says: “I really worry when we legislate things that no one understands. People can get harmed.” Numerous issues have to be worked out, according to Brawley. For one, he explains: “There is no standard way to define density.” Additionally, “even though studies suggest that density increases the risk of cancer, these cancers tend to be the less serious kind, but even that is open to question,” Brawley says. “We in medicine do not know what to do for women who have increased density.”

A study of more than 9,000 women in the Journal of the National Cancer Institute revealed that women with very dense breasts were no more likely to die than similar patients whose breasts were not as dense. “When tumors are found later in more dense breasts, they are no more aggressive or difficult to treat,” says Karla Kerlikowske, MD, study coauthor, and professor of medicine and epidemiologist at the University of California San Francisco. In fact, an increased risk of death was only found in women with the least dense breasts.

The trouble is what is known about dense breasts is murky. Asked whether he backs advising women that dense breasts are a risk factor for breast cancer, Anthony B. Miller, MD, Co-Chair of the Cancer Risk Management Initiative and a member of the Action Council, Canadian Partnership Against Cancer, and lead investigator of the Canadian National Breast Cancer Screening Study, says: “I would be very cautious. The trouble is people want certainty and chances are whatever we find, all we can do is explain.”

Women in their forties, who are most likely to have dense breasts (density declines with age) may want to seek out digital mammography. In studies comparing digital mammography to film-screen mammography in the same women, digital mammography has been shown to improve breast cancer detection in women with dense breasts. Findings from the Digital Mammographic Imaging Screening Study, showed better breast cancer detection with digital mammography. But digital mammography is not available in many areas.  Moreover, Miller explains: “We do not know if this will benefit women at all.  It is very probable that removal of the additional small lesions will simply increase anxiety and health costs, including the overdiagnosis of breast cancer, and have no impact upon mortality from breast cancer.”

Additional imaging studies sound attractive to people convinced that there is something clinically significant to find. But as I pointed out in my last post, many radiologists and breast physicians contend that there is no evidence that magnetic resonance imaging or any other imaging study aids breast cancer screening in women with dense breasts. Brawley notes: “These laws will certainly lead to more referral for MRI and ultrasound without clear evidence that women will benefit (lives will be saved.) It’s clear that radiologists will make more money offering more tests.” Miller adds: “A number of doctors are trying to capitalize on this and some of them should know a lot better.

Many Advocates Question More Tests, Statutes

Even though the “Are You Dense?” campaign has been instrumental in getting legislation on the books across the county, other advocacy groups and patient advocates want research, enhanced patient literacy about risks and benefits of procedures. Many recall mistakes made that led women down the path of aggressive procedures. In that group is the radical Halsted mastectomy, used widely before systematic study, but once studied,  found no better than breast-conserving surgery for many cancers, and bone marrow transplants, also found to be ineffective, wearing, and costly.

Jody Schoger, a breast cancer social media activist at @JodyMS, who engages women weekly on twitter at #bcsm, had this to say on my blog about the onslaught of additional screening tests:

“What is needed is not another expensive modality… but concentrated focus for a biomarker to indicate the women who WILL benefit from additional screening. Because what’s happening now is an avalanche of screening, and its subsequent emotional and financial costs, that is often far out of proportion to both the relative and absolute risk for invasive cancer. I simply don’t think more “external” technology is the answer but one that evolves from the biology of cancer.”

Eve Harris @harriseve, a proponent of patient navigation and patient literacy, challenged Peter Ubel, MD, professor of business administration and medicine, at Duke University, on his view of the value of patient empowerment on the breast density issue. In a post on Forbes, replicated in Psychology Today, Ubel argued that in cases where the pros and cons of a patient’s alternatives are well known, for example, considering mastectomy or lumpectomy, patient empowerment play an important role. “But we are mistaken to turn to patient empowerment to solve dilemmas about how best to screen for cancer in women with dense breasts,” he writes.

Harris disagrees, making a compelling case for patient engagement:

“I think that we can agree that legislative interference with medical practice is not warranted when it cannot provide true consumer protection. But the context is the biggest culprit in this situation. American women’s fear of breast cancer is out of proportion with its incidence and its mortality rate. Truly empowering people—patients would mean improving health literacy and understanding of risk…”

But evidence and literacy take time, don’t make for snappy reading or headlines, and don’t shore up political points. Can we stop the train towards right-to-inform laws and make real headway in women’s health? Can we reallocate healthcare dollars towards effective treatments that serve patients and engage them in their care? You have to wonder.


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I am a radiologist who has done breast imaging for over 30 years.
Either Laura Newman did not read the article about the 9,000 women or didn't understand it.
Dr. Gierlach, the author stated in the conclusion of her paper that: “High mammographic breast density was not associated with risk of death from breast cancer or death from any cause after accounting for other patient and tumor characteristics”. She qualified the equality of the risk of dying from cancer with fatty or dense breasts only when there was equality in all other patient and tumor characteristics, including stage and size. In other words, if a woman has a stage I cancer, she has an equal chance of dying whether she has fatty or dense breasts. Similarly, if a woman has a stage III cancer, her breast density is irrelevant to her survival.
Where density is important is in early detection. If a woman with fatty breasts presents with a stage III, 3cm cancer, she has not been having annual mammography. Otherwise the cancer would have been discovered as a stage I, probably about 1 cm or less in diameter. However, if a woman with dense breasts presents with a 3cm stage III cancer, it is very possible that she has had numerous, previous, normal, annual mammograms with the dense tissue previously obscuring the growing mass.
I have personally spoken with the author of this study. She is incensed about the deliberate misrepresentation of her work. She is a government employee, so she cannot get into a public controversy. She did privately complain to the Society of Breast Imaging and the American College of Radiology about their misinterpretation of her findings. She also has given birth less than a month ago, so she has other matters on her mind.
I'm old enough to remember the ravages of cervical cancer before the widespread use of the Pap smear. It took over thirty years from its in discovery to nationwide implementation. Its use in early detection has resulted in an 80 to 90% in mortality rate in this country.
The proponents of early detection of breast cancer are right. The sooner we can deliver the same early detection for women with dense breasts, as we presently do for women with fatty breasts, the sooner we will have similar results to those we have had with cervical cancer.

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Dr Kelly is confusing the issue by bringing in cancer of the cervix. Screening for cancer of the cervix is for acknowledged precursors, very different from screening for cancer of the breast, where cancers are the primary targets. Cervix screening is far more effective than breast screening, though at the cost of treating a large number of precursors that are not destined to progress to cancer. DCIS is a marker of future risk of breast cancer, there is no evidence that all breast cancers are preceded by detectable DCIS. Further, demonstrating that an imaging method identifies a cancer does not confirm that the outcome will be better. For this to be determined, you have to be able not only to show that method detects an earlier stage cancer, but that the detection and removal of the cancer results in reduction in the subsequent incidence of and eventually mortality from the cancer. This is why the “trials” supported by the American College of Radiology Imaging Network (ACRIN) are deeply flawed. All they are capable of demonstrating is the relative sensitivity of the methods of imaging assessed. What we do know is that the specificity of digital mammography and of ultrasound is inferior to film screen mammography, thus with their adoption there will be increase in unnecessary diagnostic tests with consequent anxiety, and very likely increase in over-diagnosis of breast cancer, thus increasing health care costs. What we do not know is whether there will be any impact on breast cancer mortality, but it seems likely that if there is any, it will be small.

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One of the reasons I brought cancer of the cervix into the discussion is that it is similar with the present breast controversy in that Dr. Papinicoloau’s method of early detection of cervical cancer with the Pap smear was accepted nationally 30 years after its publication because of opposition to it by individual physicians and the AMA in the 40’s and the early 50’s. Its acceptance occurred only after a Provence-wide study in Manitoba, even though the method was discovered in the U. S.
I authored a multi-institutional study published in European Radiology (Google: 10.1007/s00330-009-1588-y) of over 6000 women who mostly had dense breasts. These women had an automated screening ultrasound in addition to screening mammography. Ultrasound found 100% more cancers (23) than mammography alone (23). More importantly it tripled the number of small (≤ 1cm) invasive cancers (7 without ultrasound v 21 with ultrasound). Invasive cancers this small can be treated in the vast majority of instances without chemotherapy and quite possibly often without radiation therapy. Cancers this size are lethal only in extremely rare instances. A complete cost analysis has not been done, but the savings from decreased chemotherapy and radiation therapy may, or nearly may, compensate for the screening and workup costs.
If early detection of cancer has any value, it would be difficult ignore these results and prevent women from the knowledge of, and the benefits of this procedure, especially when over 100 women a day die from breast cancer in the United States. That’s approximately 20% of the women who get invasive breast cancer in this country. If we can find ½ of the invasive cancer at ≤ 1cm, as we did in our study, the mortality rate in that group found by automated ultrasound would be reduced to 1 or 2%.
Before you retort with “many small invasive cancer are indolent and grow slowly or not at all, and are therefore clinically irrelevant”, I have collected 30 instances of breast cancers less than 1 cc in volume that were recorded, but were not recognized during an automated ultrasound. Each of these cancers was subsequently measured by ultrasound, when discovered by the next ultrasound screening or by physical presentation. Eighty percent of these cancers doubled in volume in less than 1 year. Only 2 (7%) required more than 2 years to double in volume. This data will be presented at the European Congress of Radiology in Vienna in March.
Early detection of cancer whether it’s colon cancer, cervical cancer or breast cancer reduces morbidity and mortality. We, as physicians, have the obligation to inform women of their choices, and not hide information that is relevant to them making their own decisions. It is paternalistic to assume that women cannot make rational decisions, or that such information would cause undue anxiety.

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As I previously indicated, the mere detection and treatment of an early cancer does not mean that the person has benefited. A feature of screening that it has taken some time for people to understand, and many do not still, is that when you use more and more sensitive screening tests, and expand the detectable pre-clinical phase towards the cancer’s origin, you will find more and more cancers that would never have presented clinically in that person’s lifetime – over-diagnosis. One of the most important pointers to that is the fact that one of the groups of collaborators participating in the US National Cancer Institute’s Cancer Intervention and Surveillance Modeling Network (CISNET), could not model the natural history of breast cancer to match recent and existing breast cancer incidence and mortality rates until they postulated a group of limited malignant potential breast cancers that might progress to a small but detectable size and then regress after 2 years if not detected. Such cancers appeared to comprise around 40% of onset cancers and 25% of those detected by mammography. The more one seeks and the more one finds such tumors, the greater the cost and the greater the unnecessary diagnoses. It is now necessary for those interested in the earlier detection of breast cancer to take a leaf out of the book of a number of informed urologists, who are finding that a process of watchful surveillance of PSA-detected prostate cancers reduces the extent of unnecessary radical surgery, with all the complications that has brought, without harm to the patient.

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Perhaps, I did not explain this upcoming paper well enough. This is an observational study of the natural growth 26 cancers with 30 growth observations. In all of these observations, the first measurement is retrospective, since had the cancer been seen at the time it would have been removed. Two cancers were missed twice and 1 three times. In 16 of the final observations the cancer was not palpable, but rather was observed on a subsequent automated ultrasound. The periods between ultrasonic observations varied from 5 to 34 months.
The measurements were made by 3 radiologists blinded to each other’s measurements. Interval measured growth for each lesion was the average of the growth rates calculated by each radiologist.
In the 30 cancer observations, 2 cancers doubled in volume doubled in about 1 ½ months, 2 in 3 months, 10 between 4 and 6 months, 10 between 7 and 12 months, 3 between 1 and 1 ½ years, 1 at about 2 years and 2 between 6 and 7 years.
In 80% of the observations the cancers had doubled times of 1 year or less within a year. If the growth of these cancers continued at that rate their mass would octuple within 3 years. Only 7% of the cancers had doubling times long enough to be considered “over diagnosed”
The difference between observation of cancer growth and modeling growth is that the observations are reflections of the cancer growth process in the real world, often referred to as “Reality”, where as a model is at best a thetorical construct requiring corroboration by reality testing such as observation.
Our conclusion is that all invasive breast cancers must be considered dangerous and should be removed as soon as possible.

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