American College of Physicians: Internal Medicine — Doctors for Adults ®

Wednesday, October 7, 2015

Breast cancer screening: of chances and choices

A sardonic insight by Bertrand Russell deftly, if disturbingly, conveys much of what is wrong in the realm of modern health promotion, particularly where diet is concerned: “The whole problem with the world is that fools and fanatics are always so certain of themselves, and wiser people so full of doubts.” Ordinarily, I would follow the ramifications of that observation for nutrition to all the dubious places they take us, as I have before. But today, I am on a different mission; today's topic is breast cancer screening.

Russell's perception pertains here, too, if somewhat less overtly. In science, we acquire data and thus, arguably, knowledge over time. Whether or not that is tantamount to getting “wiser” is fodder for debate, but we can pretend for now that the two are approximate surrogates. While the accumulation of evidence advances understanding and occasionally leads to unassailable conclusions, it leads even more often to a new array of questions. Substituting knowledge for wisdom, Russell may have been more correct than even he intended: The more we learn in science, the more we know about how much we don't know. As a vivid and timely example, we have apparently just discovered a whole new branch of the pre-human family tree. As a more vintage illustration, relativity theory was a perfect epiphany until we learned enough to know it was imperfect. Newton's revelation about gravity was perfect, until Einstein came along.

Alas, the same is true of cancer screening. As I have noted many times over the years, cancer screening is, in the most literal sense, looking for trouble. That is a prudent and constructive enterprise when, and only when, the following criteria are satisfied:

1. Neither too few, nor too many, people are prone to the trouble. If no one gets a condition, screening for it is a waste of time and resources. If everyone gets it, then screening is pointless and routine preventive treatment makes more sense, as is the standard practice for dental caries. Screening is most useful when a condition is neither too rare nor too common.

2. The test must work well. A good test reliably finds the condition when it is there, and reliably rules it out when it is not there. In the real world, however, errors occur in both directions. A false positive is finding what isn't there; a false negative is failure to find what is. Too many of either, and the harms of screening may readily outweigh the benefits.

3. We must be able to handle the trouble. Screening is about finding a condition early, before it can progress and make itself apparent without screening. The advantage in that lies entirely with the capacity to treat the early version of the condition more effectively. If effective treatment is not available, if the condition is as unmanageable when found early as late, or when we cannot distinguish between those variants that warrant treatment and those that do not, the case for screening is unmade.

Of late, challenges to the breast cancer screening case have been encountered in each of these areas. Many women, it turns out, are prone to a very early form of breast cancer, called ductal carcinoma in situ (DCIS), which may not warrant treatment at all. The failings of mammography, both the tendency to miss cancer that's there, and the very common problem of false positives, have been put on increasingly prominent display. Doubts have been raised about a mortality benefit from breast cancer screening. Even breast biopsies have been proven fallible.

One related topic warrants special attention. A national initiative is advancing the cause of customized breast cancer screening protocols for women with dense breast tissue. A recent commentary in JAMA Internal Medicine challenges this, suggesting that practice is being driven beyond the evidence by the force of legislation. Here, I disagree adamantly on the basis not of special knowledge, but simply logic.

The authors in question argue that we don't have population-level evidence of net benefits of customized screening in cases of dense breast tissue, and they are, thus far, correct. However, consider the alternative. Since we know conventional mammography is nearly useless in women with dense breast tissue, an argument against customized screening methods is, in effect, an argument either for not screening these women (nearly 40 percent of the female population) at all, or to do so using what we know to be nearly useless methods, which is the same thing.

So, without saying it, these authors are suggesting that women with low breast density should be screened for cancer, while those with high breast density should NOT be screened. That there is no evidence at the population level to support this profound inequity goes without saying. The authors are espousing a double standard, and proposing to encumber the population with their untested hypothesis.

In contrast, arguments for (and legislation protecting) customized screening are merely an attempt to level the playing field. Whatever the net effects of breast cancer screening, they should be distributed equitably. If the prevailing view favors screening, then that view should pertain to all women.

Does the prevailing view favor screening? The answer is a qualified yes. In a beautifully thoughtful commentary, also in JAMA Internal Medicine, my colleague and leading breast cancer epidemiologist, Dr. Joann Elmore, indicates, wisely, that we are rather full of doubts. There are pros and cons to screening, and the best decisions are individualized, predicated, ideally, upon good dialogue between doctor and patient.

For quite some time, we were confident that prostate cancer screening was a good idea. The more we learned about our inability to distinguish between cases that warranted treatment, and cases where cure was worse than disease, the less certain of ourselves we became. In time, the U.S. Preventive Services Task Force, a group of highly qualified experts to which fools and fanatics need not apply, came to recommend against prostate cancer screening, concluding it was apt to confer net harm.

The Task Force, which follows the evidence fastidiously where it leads, thus far recommends for breast cancer screening in women between the ages of 50 and 74, every other year. They are inconclusive about screening in younger women, although some data suggest that benefit is seen with far more frequent (i.e., every six months) screening in premenopausal women who may be prone to cancers that progress faster.

In summary, then, the wisest (and/or most knowledgeable) people examining the issue of breast cancer screening are rather full of doubts. Personalized decisions must be made in that context. For whatever it's worth, as a married, male preventive medicine specialist, here is how it plays out in my household: I do not get screened for prostate cancer; my wife gets mammography routinely.

A final consideration is that screening, at its best, finds established trouble early; it does nothing to prevent it outright. Rates of breast cancer, and prostate cancer for that matter, are substantially lower among those who don't smoke, eat optimally, exercise routinely, and maintain a healthy weight than among those who do otherwise. Lifestyle as medicine has the potential to go beyond the early detection of trouble, to its outright avoidance; I recommend it with unqualified enthusiasm.

For now, much as we might wish it to be otherwise, breast cancer screening is a rather uncertain proposition. We have choices, and with each, chances of good or bad outcomes. My advice, like that of Dr. Elmore, is to be wise and acknowledge the tradeoffs; get good information from a physician you trust; and proceed in accord with your personal preferences and priorities.

Eventually, advances in science and technology will provide greater clarity, along with new questions. For now, we do the best we can despite our doubts.

David L. Katz, MD, FACP, MPH, FACPM, is an internationally renowned authority on nutrition, weight management, and the prevention of chronic disease, and an internationally recognized leader in integrative medicine and patient-centered care. He is a board certified specialist in both Internal Medicine, and Preventive Medicine/Public Health, and Associate Professor (adjunct) in Public Health Practice at the Yale University School of Medicine. He is the Director and founder (1998) of Yale University's Prevention Research Center; Director and founder of the Integrative Medicine Center at Griffin Hospital (2000) in Derby, Conn.; founder and president of the non-profit Turn the Tide Foundation; and formerly the Director of Medical Studies in Public Health at the Yale School of Medicine for eight years. This post originally appeared on his blog at The Huffington Post.

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Members of the American College of Physicians contribute posts from their own sites to ACP Internistand ACP Hospitalist. Contributors include:

Albert Fuchs, MD
Albert Fuchs, MD, FACP, graduated from the University of California, Los Angeles School of Medicine, where he also did his internal medicine training. Certified by the American Board of Internal Medicine, Dr. Fuchs spent three years as a full-time faculty member at UCLA School of Medicine before opening his private practice in Beverly Hills in 2000.

And Thus, It Begins
Amanda Xi, ACP Medical Student Member, is a first-year medical student at the OUWB School of Medicine, charter class of 2015, in Rochester, Mich., from which she which chronicles her journey through medical training from day 1 of medical school.

Ira S. Nash, MD, FACP, is the senior vice president and executive director of the North Shore-LIJ Medical Group, and a professor of Cardiology and Population Health at Hofstra North Shore-LIJ School of Medicine. He is Board Certified in Internal Medicine and Cardiovascular Diseases and was in the private practice of cardiology before joining the full-time faculty of Massachusetts General Hospital.

Zackary Berger
Zackary Berger, MD, ACP Member, is a primary care doctor and general internist in the Division of General Internal Medicine at Johns Hopkins. His research interests include doctor-patient communication, bioethics, and systematic reviews.

Controversies in Hospital Infection Prevention
Run by three ACP Fellows, this blog ponders vexing issues in infection prevention and control, inside and outside the hospital. Daniel J Diekema, MD, FACP, practices infectious diseases, clinical microbiology, and hospital epidemiology in Iowa City, Iowa, splitting time between seeing patients with infectious diseases, diagnosing infections in the microbiology laboratory, and trying to prevent infections in the hospital. Michael B. Edmond, MD, FACP, is a hospital epidemiologist in Iowa City, IA, with a focus on understanding why infections occur in the hospital and ways to prevent these infections, and sees patients in the inpatient and outpatient settings. Eli N. Perencevich, MD, ACP Member, is an infectious disease physician and epidemiologist in Iowa City, Iowa, who studies methods to halt the spread of resistant bacteria in our hospitals (including novel ways to get everyone to wash their hands).

db's Medical Rants
Robert M. Centor, MD, FACP, contributes short essays contemplating medicine and the health care system.

Suneel Dhand, MD, ACP Member
Suneel Dhand, MD, ACP Member, is a practicing physician in Massachusetts. He has published numerous articles in clinical medicine, covering a wide range of specialty areas including; pulmonology, cardiology, endocrinology, hematology, and infectious disease. He has also authored chapters in the prestigious "5-Minute Clinical Consult" medical textbook. His other clinical interests include quality improvement, hospital safety, hospital utilization, and the use of technology in health care.

Juliet K. Mavromatis, MD, FACP, provides a conversation about health topics for patients and health professionals.

Dr. Mintz' Blog
Matthew Mintz, MD, FACP, has practiced internal medicine for more than a decade and is an Associate Professor of Medicine at an academic medical center on the East Coast. His time is split between teaching medical students and residents, and caring for patients.

Everything Health
Toni Brayer, MD, FACP, blogs about the rapid changes in science, medicine, health and healing in the 21st century.

Vineet Arora, MD, FACP, is Associate Program Director for the Internal Medicine Residency and Assistant Dean of Scholarship & Discovery at the Pritzker School of Medicine for the University of Chicago. Her education and research focus is on resident duty hours, patient handoffs, medical professionalism, and quality of hospital care. She is also an academic hospitalist.

Glass Hospital
John H. Schumann, MD, FACP, provides transparency on the workings of medical practice and the complexities of hospital care, illuminates the emotional and cognitive aspects of caregiving and decision-making from the perspective of an active primary care physician, and offers behind-the-scenes portraits of hospital sanctums and the people who inhabit them.

Gut Check
Ryan Madanick, MD, ACP Member, is a gastroenterologist at the University of North Carolina School of Medicine, and the Program Director for the GI & Hepatology Fellowship Program. He specializes in diseases of the esophagus, with a strong interest in the diagnosis and treatment of patients who have difficult-to-manage esophageal problems such as refractory GERD, heartburn, and chest pain.

I'm dok
Mike Aref, MD, PhD, FACP, is an academic hospitalist with an interest in basic and clinical science and education, with interests in noninvasive monitoring and diagnostic testing using novel bedside imaging modalities, diagnostic reasoning, medical informatics, new medical education modalities, pre-code/code management, palliative care, patient-physician communication, quality improvement, and quantitative biomedical imaging.

Informatics Professor
William Hersh, MD, FACP, Professor and Chair, Department of Medical Informatics & Clinical Epidemiology, Oregon Health & Science University, posts his thoughts on various topics related to biomedical and health informatics.

David Katz, MD
David L. Katz, MD, MPH, FACP, is an internationally renowned authority on nutrition, weight management, and the prevention of chronic disease, and an internationally recognized leader in integrative medicine and patient-centered care.

Just Oncology
Richard Just, MD, ACP Member, has 36 years in clinical practice of hematology and medical oncology. His blog is a joint publication with Gregg Masters, MPH.

Kevin Pho, MD, ACP Member, offers one of the Web's definitive sites for influential health commentary.

MD Whistleblower
Michael Kirsch, MD, FACP, addresses the joys and challenges of medical practice, including controversies in the doctor-patient relationship, medical ethics and measuring medical quality. When he's not writing, he's performing colonoscopies.

Medical Lessons
Elaine Schattner, MD, FACP, shares her ideas on education, ethics in medicine, health care news and culture. Her views on medicine are informed by her past experiences in caring for patients, as a researcher in cancer immunology, and as a patient who's had breast cancer.

Mired in MedEd
Alexander M. Djuricich, MD, FACP, is the Associate Dean for Continuing Medical Education (CME), and a Program Director in Medicine-Pediatrics at the Indiana University School of Medicine in Indianapolis, where he blogs about medical education.

More Musings
Rob Lamberts, MD, ACP Member, a med-peds and general practice internist, returns with "volume 2" of his personal musings about medicine, life, armadillos and Sasquatch at More Musings (of a Distractible Kind).

David M. Sack, MD, FACP, practices general gastroenterology at a small community hospital in Connecticut. His blog is a series of musings on medicine, medical care, the health care system and medical ethics, in no particular order.

Reflections of a Grady Doctor
Kimberly Manning, MD, FACP, reflects on the personal side of being a doctor in a community hospital in Atlanta.

The Blog of Paul Sufka
Paul Sufka, MD, ACP Member, is a board certified rheumatologist in St. Paul, Minn. He was a chief resident in internal medicine with the University of Minnesota and then completed his fellowship training in rheumatology in June 2011 at the University of Minnesota Department of Rheumatology. His interests include the use of technology in medicine.

Technology in (Medical) Education
Neil Mehta, MBBS, MS, FACP, is interested in use of technology in education, social media and networking, practice management and evidence-based medicine tools, personal information and knowledge management.

Peter A. Lipson, MD
Peter A. Lipson, MD, ACP Member, is a practicing internist and teaching physician in Southeast Michigan. The blog, which has been around in various forms since 2007, offers musings on the intersection of science, medicine, and culture.

Why is American Health Care So Expensive?
Janice Boughton, MD, FACP, practiced internal medicine for 20 years before adopting a career in hospital and primary care medicine as a locum tenens physician. She lives in Idaho when not traveling.

World's Best Site
Daniel Ginsberg, MD, FACP, is an internal medicine physician who has avidly applied computers to medicine since 1986, when he first wrote medically oriented computer programs. He is in practice in Tacoma, Washington.

Other blogs of note:

American Journal of Medicine
Also known as the Green Journal, the American Journal of Medicine publishes original clinical articles of interest to physicians in internal medicine and its subspecialities, both in academia and community-based practice.

Clinical Correlations
A collaborative medical blog started by Neil Shapiro, MD, ACP Member, associate program director at New York University Medical Center's internal medicine residency program. Faculty, residents and students contribute case studies, mystery quizzes, news, commentary and more.

Interact MD
Michael Benjamin, MD, ACP member, doesn't accept industry money so he can create an independent, clinician-reviewed space on the Internet for physicians to report and comment on the medical news of the day.

PLoS Blog
The Public Library of Science's open access materials include a blog.

White Coat Rants
One of the most popular anonymous blogs written by an emergency room physician.

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