It also happened to be around that time that breast cancer advocacy and awareness efforts were starting to gain momentum.
We hear a lot these days about advances in the understanding of cancer biology, and about new experimental therapies.
But I sometimes find myself wondering just how much has been accomplished since the early ’90s. This post takes a look back at how far we’ve actually come in the fight against breast cancer in the past twenty years.
Promising New Leads?
I recently came across a copy of a letter I wrote back in 1994, about a year after my breast cancer diagnosis, to members of a congressional committee that was considering the budget for the following year. Here is part of what I had written:
I was diagnosed with breast cancer in June 1993 at age 35, although I was considered to be at low risk for getting the disease…I read with great interest that researchers are finding some promising new leads in their study of this and other types of cancer. Discovery of the causes of and cure for cancer may not be far away, but it all depends on our continued strong commitment to providing appropriate levels of funding for basic research.
The paragraph above still represents essentially where we are today, twenty years later. That is, we continue to hear about promising new leads yet we still know little about the causes of cancer and certainly don’t have a cure.
There have been some advances in breast cancer treatment in the last twenty years, and many women are screened each year in an effort to identify and treat breast cancer as early as possible. But together these developments haven’t been enough to make a big difference in what really matters, the number of lives lost to breast cancer. It is fascinating to read about recent advances in cancer research and the coming advent of targeted therapies and “personalized medicine”. But advances in understanding of the disease have not yet brought about transformational change either in the way breast cancer is treated today or in mortality from the disease.
Treatment and Survivorship
Primary breast cancer. There were several important new drug therapies for treating primary breast cancer that became available around the mid-1990s to the early 2000s. In 1994, the Food and Drug Administration (FDA) approved the chemotherapy drug Taxol (paclitaxel) for use after surgery for primary breast cancer. Taxol had been approved earlier for treatment of metastatic breast cancer. For HER2 positive breast cancer, the drug Herceptin (trastuzumab) has had a big impact in extending survival for many since it received FDA approval for treating breast cancer in 1998, and additional drugs have since been developed for this sub-type of breast cancer.
And in 2002, for postmenopausal women with estrogen receptor positive breast cancer, the first aromatase inhibitor was approved for use after surgery for primary breast cancer. (The drug tamoxifen, which blocks estrogen by a different mechanism, has been around since the 1970s and is still widely used in breast cancer treatment for premenopausal women.)
There have also been advances aimed at reducing “overtreatment”. The combination of breast conserving surgery with radiation became generally available in the early 1990s for most early stage breast cancer patients as an alternative to mastectomy when it was found to result in similar survival rates. Sentinel lymph node biopsy also became widely available around the same time. The sentinel lymph node biopsy is a procedure that often eliminates the need for full lymph node dissection and reduces the risk of lymphedema.
Prognostic tools such as Oncotype DX are now routinely used. These tools help doctors and patients determine when chemotherapy may not be necessary, sparing certain patients at low risk of recurrence the adverse side effects of that form of treatment.
It is really important to recognize though that, even with these positive developments, standard treatment for primary breast cancer remains essentially what it has been for decades–removal or partial removal of breasts, chemotherapy and radiation. Also, for some of the more aggressive breast cancer sub-types, including all of those in the so-called “triple negative” category that do not overexpress the estrogen, progesterone or HER2 receptors, there are still no targeted therapies available. For no sub-type is there a verifiable cure and breast cancers can recur after many years.
Metastatic breast cancer. It is estimated that 20% to 30% of early stage breast cancers eventually metastasize to distant parts of the body. Treatment of cancer that has metastasized, similar to treatment for early stage breast cancer, can include targeted treatments based on whether the tumor cells express the estrogen, progesterone or HER2 receptors. There are more chemotherapy drugs available to treat metastatic disease today than there were twenty years ago, and they are often given in succession–as one ceases to work for a patient, another one is tried. But most of these drugs are very toxic with sometimes very severe adverse side effects, and they are not a cure.
Long-term side effects. In addition to the immediate side effects of treatment, breast cancer patients often must cope with sometimes longer-term problems including anxiety, depression and fatigue, which can have a big impact on their quality of life. Researchers report there is a growing consensus that psychosocial care should be integrated into routine care but there is a long way to go to make this a reality for all breast cancer patients.
Screening and Prevention
A major study on breast cancer screening, published in April 2014 in the Journal of the American Medical Association (JAMA), reviewed what we know about the benefits and harms of screening mammography from the many clinical trials and other studies conducted over the last 50 years.
The JAMA article reported that the available evidence overall shows that mammography screening is associated with some reduction of breast cancer mortality. The benefit of mammography was found to be greater for women who are at higher risk because they are older or have other risk factors such as a family history of breast cancer.
In addition, the study found that as a result of screening some women will be treated unnecessarily for a condition that would never have been life-threatening. Screening mammography can lead to diagnosis of a non-invasive, very early stage breast cancer known as ductal carcinoma in situ (DCIS) or other extremely small early stage cancers that will never become life-threatening. However, since there is no way currently to determine whether these conditions will indeed become life-threatening, those diagnosed with them are generally treated with surgery and radiation, and subjected to all of the risks that these treatments entail.
Today, the same as twenty years ago, we still have no screening methodology for breast cancer that can detect pre-cancerous changes when it is possible to intervene to prevent actual cancer from developing. Mammography is sometimes portrayed as preventative screening but in fact it is not able to identify pre-cancerous changes–in the way that a PAP smear does for cervical cancer or a colonoscopy does for colon cancer–at a stage when they can be removed and the development of cancer prevented.
Just like twenty years ago, breast cancer prevention remains an under-studied area. We still don’t understand the initiating causes of breast cancer or how to intervene to prevent it. We still talk about causes of breast cancer almost entirely in terms of “risk factors” or associations. Inherited genetic mutations are understood to increase risk substantially for those that have them, but such inherited genetic mutations are present in less than 1% of the population and account for only about 5%-10% of breast cancer cases.*
Mortality Rates and Ethnic Disparities
A substantial decline in deaths from breast cancer would be the result we’d hope to see from the improvements in treatments and increased screening for early breast cancer over the last twenty years. Unfortunately, that hasn’t happened.
What we have in seen instead is a moderate overall decline in breast cancer mortality rates since the early 1990s. As reported by the American Cancer Society (ACS), after slowly increasing between 1975 and 1990, breast cancer mortality overall decreased by 34% between 1990 and 2010.* But even with this modest decline, it is estimated that approximately 40,000 women and men die from breast cancer annually in the United States.
And mortality rates have not declined equally across ethnic groups. The ACS notes that a striking divergence in long-term breast cancer mortality trends between African American and white women began in the early 1980s. By 2010, breast cancer mortality was 41% higher in African American women than white women.
Advances in Research
It’s fascinating to read about recent advances in breast cancer research and in cancer research generally. Cancers are increasingly understood less in terms of where in the body they originate and more in terms of the molecular characteristics that drive them. Countless potential new therapies are being studied that would target these drivers.
The hope is that these potential therapies would be both “targeted” and “personalized”. They would be targeted in the sense that they would block cellular processes that drive the cancer while sparing normal cells, thus minimizing adverse side effects. They would be “personalized” in the sense that each patient’s treatment would be based on the molecular profile of his or her cancer.
Unfortunately, for breast cancer and most other types of cancer, these next generation targeted therapies have not yet come to fruition. Translating advances in basic science to clinical application is a complex and lengthy process often ignored in news reports which frequently imply that these potential advances are reality today.
In addition, newer cancer medications are often extremely highly priced, sometimes putting them out of the reach of patients who need them. Many patients struggle to pay for their medications and some are even forced to declare bankruptcy.
What will it take for real progress to be made? And how can we make sure that we don’t look back twenty years from now and still say “this isn’t the kind of progress we expected to see in two decades”?
It seems that the ultimate goal is probably not so much a single cure as it is several things. First, it is having much more effective and less toxic ways to treat cancer when it does occur so that we can prevent deaths from cancer. It is making sure that everyone who needs those treatments has equal access to them. And, equally important, it is having a true understanding of the causes of the various types of cancer so we can take effective measures to prevent them.
I fervently hope that meaningful progress towards these goals can be made in the not-too-distant future. It will be the result of the hard work of the many dedicated scientists, researchers and clinicians who focus on this effort 24/7. But for that kind of progress to occur, there will probably need to be a greater level of general awareness that results achieved to date have been more limited than many people think in terms of what really matters, saving lives.
*Source: American Cancer Society, Breast Cancer Facts & Figures 2013-2014
Breast Cancer Quality of Life Issues: A Researcher Asks “Are We Doing Better?”
Recent Breast Cancer Screening Studies: What Are the Take-Home Messages?
Why Do New Cancer Drugs Cost So Much?
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