For many years, prostate cancer, a men’s cancer, received far more research interest and money than breast cancer. However, in recent years breast cancer has become much more high profile, and both the number of organizations dedicated to the disease and the amount of money spent on breast cancer research has expanded. It may be no coincidence then that the incidence of breast cancer among women in the United States has started to decline over the past few years after rising steadily for several decades. Several avenues of research into this disease are yielding results, and there is more to come in the near future. Below is an overview of some of the recent medical developments in breast cancer research followed by links to some recent scientific and news articles about breast cancer.

Breast cancer prevention

Nearly every day there are stories in the newspaper about something that increases or decreases the risk of cancer. While one study may provide evidence that a certain factor affects cancer risk, researchers are usually not convinced until several studies conclude the same thing. A sample of some of the things that scientists are investigating as potential preventive therapies for breast cancer follows:

Retinoids

Retinoids are natural antioxidant compounds that are related in structure to vitamin A. Retinoid molecules have the ability to kill breast cancer cells in a lab dish, which suggests they might have the same effects inside the body. So far, studies of women who take vitamin A have not shown any effect on breast cancer incidence. However, one study did show that in a select group, more vitamin A seemed to reduce breast cancer risk. The women found to benefit from the vitamin were premenopausal with a family history of breast cancer. More research on retinoids and breast cancer is forthcoming.

Flaxseeds

Flaxseeds are the seeds of the flax plant, the same plant whose fibers are used to make linen fabric. These seed are used to make a type of vegetable oil called linseed oil. Flaxseed is high in omega-3 fatty acids and in lignan, a naturally occurring compound that lowers circulating estrogens in the body. Lignans are a type of phytoestrogen, which are molecules made in plants that have a similar structure to estrogen. This means that in the body, lignans can fool the estrogen-producing cells into thinking that more estrogen is around than there really is, which makes these cells reduce the amount of estrogen they produce. This is very similar to the way that the hormone therapy tamoxifen works.

Studies of breast cancer cells in a lab dish show that the lignans from flaxseeds can make the cancer cells less motile and sticky, two properties that normally help cancer cells to spread. In animals such as mice, a diet that includes flaxseeds appeared to reduce the growth and spread of several types of cancer including breast cancer. A limited study in women with breast cancer showed that flaxseeds made the cancer cells less aggressive.

Physical activity

While obesity is a risk factor for developing breast cancer, physical activity seems to be somewhat protective against the disease. Several studies have suggested a beneficial relationship between activity level and breast cancer and a recent retrospective study concluded that women with the highest total adult lifetime activity were 20 percent less likely to have developed breast cancer than the least active women. The women who were most active had about a 25% lower risk of developing breast cancer. Exercise seemed to benefit everyone, no matter what their weight. Also, women in their 50s who only started exercising after age 50 had a 30- 40% lower risk of developing breast cancer than those in their 50s who did not exercise. This is just one of many reasons to be physically active; it is never too late to reap the health benefits.

NSAIDs

The non-steroidal anti-inflammatory drugs (NSAIDs) such as aspirin and ibuprofen have known benefits for those with heart disease. Some recent evidence indicates that these common drugs may also be useful in the prevention and even the treatment of breast cancer.

Breast cancer tissue produces abnormally high levels of a molecule called COX (short for cyclo-oxygenase) and the NSAIDs are COX inhibitors. A retrospective review of several studies of NSAIDs suggested that their use was associated with a moderate decrease in breast cancer risk. The study suggested that the NSAIDs were effective in preventing the growth of both estrogen receptor-positive (ER+) tumors, which currently can be treated with drugs such as tamoxifen, and estrogen receptor-negative (ER-) tumors, which are harder to treat. NSAIDs have some side effects, including stomach bleeding so they are not for everyone, and the optimal dose for cancer prevention has yet to be determined.

Breast cancer treatments

If you are diagnosed with cancer, your doctor may order special lab tests on the breast tissue that was removed. These tests help your doctor learn more about the cancer and plan appropriate treatment. New developments on this front include tests for the hormone receptors that are present in the cancer cells. These tests can help determine how to best treat the tumor.

Hormone receptor test

The hormone receptor test determines whether the cancer tissue has receptors for the hormones estrogen or progesterone, which determines if hormone therapy is appropriate. A cancer is called “ER-positive” if it has receptors for the hormone estrogen and called “PR-positive” if it has receptors for the hormone progesterone. Breast cancers that are either ER-positive or PR-positive, or both, tend to respond well to hormone therapy (such as tamoxifen) because they rely on levels of these hormones to grow. If you are treated with medicine or surgery that reduces the estrogen in your body or that keeps estrogen away from the receptors, the cancer may stop growing entirely. If the cancer has no hormone receptors, hormone therapy is not appropriate.

HER2-neu test

This test shows the level of the HER2-neu protein expressed in the cancer tissue. HER2-neu is a growth factor receptor through which cancer cells are stimulated to continue growing and dividing. If the cancer cells have high levels of this protein, it tends to spread faster and may recur after treatment. It also means that the cells depend on signals passed through the HER2-neu receptor to grow. If so, the cancer can be treated with biological therapy such as herceptin or lapatinib (Tykerb), which blocks signaling though the HER2-neu receptor. Around 25% of breast cancers have elevated levels of HER2-neu and so can be treated with biological therapy.

Breast cancer risk factors

Smoking

Some studies show no link between cigarette smoking or exposure to secondhand smoke and breast cancer, while others suggest that smoking increases breast cancer risk. Exposure to secondhand smoke may also increase risk but researchers haven’t yet established a clear link. More studies will hopefully clarify the relationship between smoking and breast cancer but one thing is clear: there does not need to be any elevated breast cancer risk from smoking to make smoking hazardous to your health. Quitting smoking is always a good idea.

Hormone replacement therapy (HRT)

Hormone replacement therapy is a well established risk factor for developing breast cancer. Even so, researchers continue to examine exactly how much of an added risk HRT confers, and which types and length of treatment carry the biggest risk. Researchers have established that four or more years of combination HRT with both estrogen and progesterone increases breast cancer risk, but new research shows that using HRT for only 3 years roughly tripled their risk of two types of breast cancer. While some women really need HRT to get through the period of menopause, it is best to limit the use of HRT to as short a period of time as possible.

Genetics of breast cancer

For about 90% of breast cancer cases the cause is unknown, while only about 5 - 10% of new breast cancers are inherited. The most important genes for breast cancer risk are BRCA1 and BRCA2; women who have either of these genes are at a 30-40% increased risk for breast and ovarian cancer. However, these are not the only genes involved in breast cancer risk.

Another gene that was recently determined to cause susceptibility to breast cancer is the ataxia-telangiectasia gene (ATM). When inherited from both parents, this gene causes a disease whose hallmark is incredible difficulty maintaining balance. But when only one copy is inherited, it leads to an increased risk of developing breast cancer. The gene appears to confer increased susceptibility to mutations from radiation, which likely causes the increased breast cancer risk.

Another recently discovered gene is the CHEK2 gene. The CHEK2 mutation is estimated to account for about 18% of hereditary breast cancer cases probably by interacting with other unidentified genes to increase breast cancer risk. More work on this gene and its role in breast cancer is needed to establish its role in breast cancer susceptibility.

Other genetic mutations associated with increased breast cancer risk include the p53 tumor suppressor gene, the ESR1 and ESR2 genes which have been found to be associated with increased risk of breast cancer in Ashkenazi Jewish women over age 50, and the ICAM (intercellular adhesion molecule) genes which regulate how well cells stick together.

Advocacy Groups

The number and size of breast cancer advocacy groups has grown immensely in the past 20 years. A disease that was once thought of as shameful and something to be hidden from the neighbors is now a rallying cry for the empowerment of women everywhere. It is impossible to quantify the way that changing social attitudes can beneficially affect disease outcomes but there is no doubt that many more women are alive today because of the health care workers, survivors, friends, and loved ones who make up these groups. Today, more than ever before, a woman can come home from the doctor with a breast cancer diagnosis and immediately find an overwhelming number of resources for support as well as specific information and insight from women with similar experiences.

Links to recent breast cancer news and developments

Breast cancer news on Science Daily, a digest of recent science research news.
http://www.sciencedaily.com/news/health_medicine/breast_cancer/

PubMed is a U.S. National Institutes of Health search engine that covers all research published in medical and bio-scientific journals.
http://www.ncbi.nlm.nih.gov/PubMed/

PubMed Central is the National Institutes of Health free digital archive of biomedical and life sciences journal literature.
http://www.pubmedcentral.nih.gov/

Medline Plus, a service of the NIH, has links to recent breast cancer news stories.
http://www.nlm.nih.gov/medlineplus/breastcancer.html#cat57

The U.S. Food and Drug Administration Center for Biologics Evaluation and Research is the government agency charged with reviewing and approving applications for new drugs and medical devices and their website ahs information about recent developments in these areas.
http://www.fda.gov/Cber/index.html

Information about clinical trials

If you are interested in finding out more about clinical trials for breast cancer, the National Institutes of Health has a clinical trials website at http://clinicaltrials.gov/.

To find a clinical trial being conducted in your area, visit the Healia Clinical Trials Search page.