Watching Women's Health

Every other year mammograms for age 50 and over?

Anyone in touch with the news knows there has been heated discussion about the recent US Preventive Services Task Force breast cancer screening recommendations. The heat has been largely focused on the suggestion that routine mammograms be deferred until age 50. Less remarked on is the further recommendation that mammograms be done every other year rather than yearly.

How the the task force arrive at this?

They relied on a study that used six independently developed models to calculate the "efficiency" of 20 different mammogram screening strategies. The differing strategies started and stopped mammograms at various ages, and did mammograms either annually or every other year.

A screening strategy was considered "efficient" if it led to an improved health outcome (compared to no screening) and consumed fewer resources (compared to other screening strategies).

An "improved health outcome" was life-years gained or fewer deaths from breast cancer. Starting screening at younger ages led to more life-years gained, while continuing screening through older ages led to fewer deaths from breast cancer.

When the researchers ranked the different strategies, all 6 models predicted the most efficient approach was screening every other year.  The health outcomes were close to those achieved with annual mammograms and there almost 50% were fewer false positives.

In support of using models for this analysis, the researchers said:

Our results are also consistent with current knowledge of disease biology. Slow-growing tumors are much more common than fast-growing tumors, and the ratio of slow- to fast-growing tumors increases with age, so that little survival benefit is lost between screening every year versus every other year. For the small subset of women with aggressive, fast-growing tumors, even annual screening is not likely to confer a survival advantage. Guidelines in other countries include biennial screening. However, whether it will be practical or acceptable to change the existing U.S. practice of annual screening cannot be addressed by our models.

Some have objected to the cold-hearted approach of using models to evaluate screening for breast cancer. The study using models looked at breast cancer screening from a societal, rather than individual perspective.

When physicians see individual patients, subjective values are important. While physician organizations (like the American College of Obstetrics and Gynecology) evaluate these recommendations, many women will continue to have yearly mammograms, starting at age 40.

Physicians need time in clinic to advise our patients about the timing of mammograms. And we all must be able to adjust our medical opinion and advice as new information becomes available and is analyzed.

Unfortunately, early detection helps only a subset of women with breast cancer. The greatest benefits will come when we learn more about how to prevent breast cancer.

Our society will continue to study and discuss how best to allocate breast cancer resources among prevention, early detection and treatment efforts.

New breast cancer screening guidelines allow for individual decision-making

Who would have thought a federal task force with an unpronounceable acronym for a name could stir up so much controversy with one journal article?

Like most physicians who care for women, I was a bit surprised by substantial changes in the US Preventive Services Task Force (USPSTF) screening recommendations for breast cancer released last week.

This past week, I read both the 2002 and 2009 reports, and the evidence reviews they are based on. Here's my take on the new recommendations. This is a longish discussion, so stay with me for a few minutes.

In general accord with the 2002 statement, most US physicians have been recommending mammograms every 1-2 years starting at age 40 and then annually from age 50. We consider clinical breast exams to be an important part of a woman's annual physical and encourage our patients to do regular self breast exams.

For women at average risk of developing breast cancer, the USPSTF now says the best current evidence supports mammograms every other year, starting at age 50 and possibly ending at age 74. The task force points out the usefulness of clinical breast exams has not been proven.

And, on the basis of two large studies, the report also states doing self breast exams does not lead to a lower risk of dying from breast cancer.

Mammogram screening benefits and harms

In making these recommendations, the task force calculated benefits and harms from breast cancer screening. The identified benefit was reduced risk of dying from breast cancer. The harms included false positive results leading to unnecessary further testing and overdiagnosis of non-life threatening cancers.

The task force based its mammogram recommendations on a review that estimated how many women in different age groups would have to have regular mammograms to prevent one woman's death from breast cancer.

For women in their 40s, one life is saved for every 1904 screened women. In comparison, one life is saved by screening 1339 women in their 50s and 377 women in their 60s. The benefit is obviously greatest for women in their 60s.

Here is the review's concluding paragraph:

Our meta-analysis of mammography screening trials indicates breast cancer mortality benefit for all age groups from 39 to 69 years, with insufficient data for older women. False-positive results are common in all age groups and lead to additional imaging and biopsies. Women aged 40 to 49 years experience the highest rate of additional imaging...  Mammography screening at any age is a tradeoff of a continuum of benefits and harms. The ages at which this tradeoff becomes acceptable to individuals and society are not clearly resolved by the available evidence.

For physicians who regularly read the medical literature, the USPSTF statement does not come out of the blue.  The effectiveness of screening tests in preventing cancer deaths is regularly addressed in journals we read.

After the report was released, most of the discussion has concerned mammograms not being automatically recommended for women in their 40s.

Screened women in that age group did have a 15% reduction in breast cancer mortality, which seems worthwhile to most physicians. However, women in their forties had significantly more false positives, leading to further imaging and, less often, biopsies.

The task force included anxiety with further testing as a harm from screening.  Many women have spoken up to say they can deal with anxiety to gain a benefit from screening, and they think the task force report was condescending.  Here's what the report said:

False-positive results are common with mammography and can cause anxiety and lead to additional imaging studies and invasive procedures (such as biopsy or fine-needle aspiration). False-positive results and accompanying additional imaging studies are more common in younger women... Anxiety, distress, and other psychosocial effects can exist with abnormal mammography results but fortunately are usually transient, and some research suggests that these effects are not a barrier to screening... Other potential harms, such as pain caused by the procedure, exist but are thought to have little effect on mammography use.

How the task force incorporated these concerns about anxiety and pain into their recommendations is not clear to me.

Another concern is that most of the data comes from outside the US, and may not accurately reflect our current mammography results and breast cancer treatment success.

Mammograms and breast biopsies are only as good as our ability to interpret their results. Some of the most exciting breast cancer research involves individualizing breast cancer treatment by identifying the biological behavior of a woman's specific cancer.

When and if individualized treatment is available, it will spare many women from being overtreated for breast cancer. This research could also save lives of women who have cancers that may require unusually aggressive treatment.

If we significantly back off from our screening programs, fewer women may benefit from these advances.

The review article acknowledges this:

Breast cancer is a continuum of entities, not just 1 disease that needs to be taken into account when considering screening and treatment options and when balancing benefits and harms. None of the screening trials consider breast cancer in this manner. As diagnostic and treatment experiences become more individualized  and include patient preferences, it becomes even more difficult to characterize benefits and harms in a general way.

What to do now

So how will I incorporate the USPSTF report into my practice? The task force made recommendations for the general population, but in clinic, I make recommendations to individuals.

The first step is assess a woman's risk for developing breast cancer. In my clinic, I use the Gail model and any available information about a women's breast tissue density.

For now, I will make sure average-risk women in their 40s are aware that mammogram false-positives are higher for them than for older women. However I will also tell them having mammograms reduces their risk of dying from breast cancer and that today's evidence for and against screening is not the last word. Then we can make a shared decision about mammograms.

As the task force itself says:

The USPSTF recognizes that clinical or policy decisions involve more considerations than this body of evidence alone. Clinicians and policymakers should understand the evidence but individualize decision making to the specific patient or situation.

That's what I do now and will continue to do. 

In a future post, I'll write about mammograms for women in their 50s and older, as well as clinical and self breast exams.

Considering the end of life

A good friend died recently, so I've been thinking a lot about the ultimate health concern — dying.

It is, of course, a hard thing to contemplate, which is why most of us, even physicians, shy away from it. Our reluctance to think about and discuss the inevitable — as individuals, as medical professionals and as a society — means many of us will miss the experience of "dying well".

Dying Well, written by Ira Byock, powerfully describes his experiences as a Montana hospice physician. He says the process of dying can lead to personal growth and fulfillment.

Without adequate medical care, dying can be horrible. With skillful medical care and attention to the personal experience of the patient and the person's family, dying can be made bearable. When the human dimension of dying is nurtured, for many the transition from life can become as profound, intimate and precious as the miracle of birth.

This is not just wishful thinking — these are words Byock backs up professionally every day as he cares for dying patients and their families.  After caring for his dying father at home while in his medical training, Byock subsequently devoted his career to hospice care.

Many people jump from the concept of dying well to the concept of physician-assisted suicide. What Ira Byock and his colleagues do makes suicide as unreasonable for dying patients as it is for everyone else .

Byock says most people do not want to die in pain, do not want to die alone and do not want to lose their personal autonomy and dignity in death. All this can be accomplished with what we know now. If dying patients are cared for in a nurturing way, most can die at home, in peace with their families.

But this takes planning and resources. As Byock says,

...good deaths [are] not random events or matters of luck; they [can] be understood and...fostered.

Dollars that might be spent for intensive, yet futile, medical care in a hospital can be diverted to home care and hospice support. Our current health care system is poorly equipped to do this as it still favors reimbursing pointless end-of-life interventions for the dying, rather than nurturing care at home. Byock's book was published 12 years ago and we have made only a little progress with this universal health concern since he wrote Dying Well. 

Few of us will get a chance to do this last event over. My mother-in-law did. In her early seventies, she had a massive hemorrhagic stroke and spent a few weeks in the hospital, mostly in an inhospitable intensive care unit. She made an improbable recovery and returned home to her usual life.

Two years later, this most rational of women was diagnosed with an inoperable brain tumor. In the time since her stroke, she had made clear to the closest family member that she wanted no intervention for a terminal condition if it exchanged quality of life for only a little longer life. A few months later, she died in peace, at home, just as she chose.

With recent and earlier losses in mind, my husband and I are updating our wills and medical directives. It is an odd experience to read one's will, but far easier to do when death is presumably distant rather than imminent. We are taking particular care with expressing our end-of-life wishes.

Whether one believes in an afterlife or not, dying is a major event, and if circumstances allow, we want some say in how it takes place.

Most of us want pretty much the same things when we inevitably die. Let's hope our health care system can adapt itself to those wishes.