The information about breast cancer keeps on coming.
We have witnessed a number of new research reports over the past six months that would have anyone interested in the subject of breast cancer reeling from the various—and at times conflicting—messages contained in these reports.
Now, we have another article published in the current issue of Cancer which shows that mammography rates have fallen precipitously from 2000 to 2005.
If you are a regular reader of this blog, you might be asking, “What’s new about that?” After all, we have been discussing the various reports about the decreasing incidence of breast cancer and the decrease in screening mammography for some time.
In fact, this new study adds further strong confirming evidence that we are facing significant challenges when it comes to the early diagnosis of breast cancer.
This new report, which is authored by investigators from the National Cancer Institute (NCI) and the Centers for Disease Control and Prevention (CDC), found that mammography screening rates dropped nearly 4% from 2000 to 2005.
This drop was found in many different groups of women, irrespective of age (see comment below), insurance, demographic factors, etc.
Of particular note was the drop in mammography screening in women between the ages of 50-64, who are generally the highest utilizers of mammography screening. In this group, the decline was 6.8% over the 5 year time frame.
As I mentioned, we have been hearing a lot of information about breast cancer incidence and mammography rates over the past 6 months. In fact, there have been concerns about these issues for some time.
In a report my colleagues released in January of 2006 in our journal CA: A Cancer Journal For Clinicians, there was a brief comment noting that there was accumulating evidence that mammography rates were dropping.
This past September, in our annual report to the nation, my colleagues (and other collaborators) reported a 4.8% decline per year in the incidence of breast cancer from 2000 to 2003.
In my blog at that time, I noted that the decline could be due to the decrease in hormone replacement therapy or the decrease in the use of screening mammograms
Then, in December 2006, researchers made a presentation at a breast cancer conference in San Antonio that a detailed analysis of a national cancer database called SEER showed there was a declining incidence of breast cancer over roughly the same time period.
The press stood up and took notice of that presentation, and there were numerous reports on the topic in the national media.
In late January 2007, the Centers for Disease Control and Prevention (CDC) reported that a nationwide telephone survey showed, for the first time, a significant decline in the use of screening mammography between 2000 and 2005. The decline, reported to be 1.8% in women age 40 and over who reported having a screening mammogram sometime in the past two years, didn’t seem like much.
At that time, I reported in my blog that those numbers were in fact substantial, and suggested through a crude analysis that thousands of breast cancers were present but not being diagnosed since fewer women were having screening mammograms.
Basically, if you don’t look for an early breast cancer, you won’t find it.
The problem is that if you don’t find breast cancer early through a screening mammogram, it will eventually grow into a more serious cancer which will be found later. Then, the cancer has a greater chance of being larger. It also has a greater probability of spreading to the lymph nodes under the arm, or worse yet, to other parts of the body.
Each step along this path means a lower chance of cure. It means that we are going backwards in our progress in the treatment of breast cancer, instead of going forward to improve the outlook for the thousands of women who are diagnosed with this disease every year.
To continue our review, this past April there was an article in the New England Journal of Medicine that reported further details of the December presentation.
Now, the researchers noted, there was a steep decline in breast cancer diagnoses that began in 2002, almost immediately following a July report in the Journal of the American Medical Association that reviewed the harms of combination hormone replacement therapy (HRT) when used for the relief of symptoms in post-menopausal women.
These researchers suggested several reasons the drop in breast cancer diagnoses occurred, but came to the conclusion that, given the almost direct parallel drop in breast cancer and number of hormone prescriptions filled, that the decrease in hormone utilization was the primary factor.
Then, a couple of weeks ago, my colleagues at the American Cancer Society published a study which highlighted the fact that the decrease in breast cancer incidence actually started before the HRT warnings were sounded in 2002.
Although they concluded that there were multiple reasons for the decline in breast cancer diagnoses, another factor that had to be given serious consideration was the fact that, after many years of increasing utilization of screening mammography, perhaps there had been in fact a “plateau” effect given the high utilization of mammography by eligible women.
To support this conclusion, they cited survey data that showed that mammography utilization rates had remained stable at about 70% over several years, while the incidence of breast cancer had been declining. They also noted that the decline was primarily confined to smaller breast cancers (less than 2 cm in size), and that the rate of regional spread to lymph nodes and the rate of women diagnosed with more advanced disease had remained stable.
So, if mammography continued at a “steady state” rate, the drop in incidence was most likely due to the fact that there were fewer breast cancers to be found. Thus, a “plateau” in new diagnoses had been achieved.
What makes the current Cancer report stand out is that the survey to back up their observations that the rate of screening mammography was indeed falling was based on a more representative, nationwide, face-to-face interview process. This approach is considered to be more accurate and representative of what is really going on in the United States with respect to several health behaviors.
The data is distressing since it shows a decline in screening mammograms that cuts across almost all ethnic, age, and other demographic groups.
My interpretation of these various studies, as reported several weeks ago and including the current report, is that there are likely several different factors responsible for the decline in breast cancer diagnoses.
Perhaps it is partially the plateau effect.
Perhaps the difficulty in accessing quality, qualified mammography facilities is playing a role.
Perhaps decreased insurance coverage is playing a role. We know from other studies that screening rates for several cancers are much lower in people who do not have health insurance, and who do not have access to quality, consistent primary care.
There probably is an impact from the decreasing use of combination HRT by postmenopausal women (recalling that the impact of HRT on the incidence of breast cancer was primarily in women who still had an intact uterus, and therefore were treated with combination HRT which included estrogen and progesterone. Women who have had a prior hysterectomy--and are not at risk of uterine cancer from HRT—can take estrogen alone. In that circumstance, the risk of breast cancer is not increased in a woman who is not known to be at increased risk of developing the disease).
The problem here is that stopping combination HRT may slow down the growth of a breast cancer, but probably does not make it go away completely. If the growth is simply slowed, then many of those women will eventually discover that particular breast cancer—which is already in development--but at a later date.
The issue here is that the fall off in breast cancer diagnoses so soon after the decrease in HRT is not likely due to a real decrease in the initiation of new breast cancers. That impact is relatively modest, and will take several years to have an impact on the rate of breast cancer incidence.
The immediacy of the HRT effect seen in the April report likely reflects other factors. It was simply too quick.
What about the possibility that women simply aren’t seeing there doctors once they stop taking their hormones? After all, if so many women were taking those medications, then they had to see their gynecologists or other primary care health professional at least once a year to get their prescriptions refilled.
And, we know from other studies, that the recommendation of a primary care health professional is probably the single most important stimulus for following cancer screening recommendations.
The logical conclusion is that if you don’t see your doctor, you don’t hear the recommendation to get a screening mammogram.
I noted in a previous blog discussing the May report that the decrease in breast cancer incidence, although almost universal in age-specific groups of women age 50 and older, was not so evident in women between the ages of 40 and 49.
In fact, in women between the ages of 40-44, there had been little if any decline in breast cancer incidence. In women ages 45-49, the data suggested a much slower decline in breast cancer diagnoses beginning in about 1996.
The current paper shows a strikingly similar pattern. In the 40-49 age group, the decline in mammography rates in the 40-49 year old age group was 0.7%. This is still a concern, but much less than the corresponding drop in women ages 50-64, which was 6.8%.
My thoughts? If you are 40-49, you are probably still seeing your gynecologist every year for your birth control pills and/or your cervical cancer screening test. Along with that visit comes a recommendation to get a mammogram.
Once you are post-menopausal, and you are not taking HRT, then you don’t feel as compelled to see your doctor. No visit, no recommendation for screening.
The highest rate of mammography screening in the current NCI report was a stunning 85.6% in 2005 for women who had seen their gynecologist in the past year. (It had been 87.5% in 2000, so there was a decline of about 1.9%.)
For women who had not seen their gynecologist in the preceding 12 months, the data from 2000 showed that 59.6% of these women had a mammogram within the preceding two years. In 2005, if a woman had not seen her gynecologist in the prior 12 months, only 54.6% had a screening mammogram. That’s a fall off of 5%.
(What the data does not tell us is what percentage of women actually had visited a gynecologist during the preceding year. I think it is also important to emphasize that this survey asked only about a mammogram in the prior two years. The American Cancer Society recommends a screening mammogram every year, so I suspect the number who actually follow our recommendation is much less than these percentages, which is cause for additional concern.)
Why is this such a problem in my opinion?
Primarily, all of this information muddles the water so to speak when it comes to giving a clear, concise recommendation about what a woman needs to do to protect her health.
I call this state of affairs “clutter and clatter.”
Experts with different, well-intentioned opinions about a problem give ordinary folks an excuse not to take action.
Arguments over the effectiveness of mammography (including the recent pronouncements from a leading medical organization regarding mammograms in women ages 40-49), the impact of hormones, and whether there is a saturation effect from screening mammograms are examples of such messages.
These are serious issues, and each needs to be addressed. But the end result is that we send mixed messages. And the result is that lives are likely at risk.
Here is the way I look at this complex set of facts:
1) I believe that mammograms save lives.
The American Cancer Society recommends that a woman at average risk should have a mammogram and clinical breast exam by a health care professional once every twelve months beginning at age 40. (Women at high risk should be aware of their unique situation, and the recommendations that apply to their particular circumstance.)
Why do I believe this?
Notwithstanding all of the academic arguments, the reality is that death rates from breast cancer have been declining since the early 1990s, despite a continuing increase—until recently—in the numbers of cases diagnosed every year. And that decline, as reflected in the SEER database, includes women ages 40-49.
2) There may well have been a plateau effect from the “saturation” levels of mammography, as noted earlier.
3) I suspect that some women are in fact becoming complacent when it comes to getting a mammogram.
Mammograms aren’t easy to get. They require making an appointment, getting the test, and having some (or a lot of) discomfort. They require a possible series of tests if there is anything suspicious on the mammogram (we call it “false-positive), which means more anxiety and concern.
If you have done this for a number of years, it becomes easy to skip a year or two and ignore the potential consequences.
This is not a good idea.
4) There is no question that the decline in the use of combination HRT is associated with a decline in breast cancer diagnoses.
This is probably due to two primary factors: a) the influence that HRT may have on the growth rate of an existing cancer, and b) the sad reality that women who are no longer taking hormones—primarily those in the 50-64 year old age group—aren’t seeing their gynecologists for regular annual exams.
I don’t think that the third factor—the influence of combination HRT on the primary development of a new breast cancer—has had time yet to have a real impact on the incidence of this disease.
3) The “saturation effect” notwithstanding, there has been a precipitous decline in the rates of screening mammograms, which means that fewer breast cancers are being discovered each year. My personal estimates are that these cases are in the thousands. These cases are not going away. They are more likely not being discovered.
What this means is that we have a crisis approaching in the diagnosis, treatment and ultimately survival of women with breast cancer.
I am ordinarily not given to being an alarmist, but I know what breast cancer was like in the 1960s and 1970s before the widespread use of screening mammograms, and I don’t want to go back to the past to see the results of the future.
If my sense of the situation is correct, this crisis is going to lead over the next several years to an increased frequency of breast cancer diagnoses at later stages, which will translate into an increased number of deaths from this disease. This is going to occur at a time when we should have been seeing an increase in the use of screening mammography, and a continued improvement in our ability to provide more women effective, life saving treatment with continued improvement in survival.
We are now well into the cycle from the time the first alarm bells were sounded over a year ago.
Now, we have overwhelming and convincing evidence that the gains we made (and needed to continue to make) in encouraging women to have an annual mammogram are slipping away at a significant rate.
The American Cancer Society is currently sponsoring a nationwide advertising campaign to encourage women to get a screening mammogram.
But all of the advertising in the world isn’t going to make much difference to women, unless they personally understand how important this test is for their health and their lives, and take the recommendation to get a screening mammogram every year to heart.
At a time when we need more action—to make certain quality facilities and trained radiologists are available, to be certain that financial considerations are never a barrier for a woman to be screened or treated for breast cancer, to be certain that women understand the importance of this test for their health—we are faced with increasing barriers, confusion and complacency.
There is no time like the present to renew your commitment to your health, to yourself, to your family, to those who love you, to those who know you.
The last thing I want to write several years from now is that I was correct in my prediction that breast cancer diagnoses at a later stage increased, and that ultimately breast cancer deaths increased.
The last thing I want to write was that we recognized the problem and did nothing about it.
That would be the saddest blog of all.