Does living better mean living longer?

Studies look at link between stress and cancer

David Spiegel, MD

February, 2004

Living well is the best revenge, and it may help you live a little longer, too. This is what researchers are now investigating, as they look at the link between how women manage stress and their ability to rebound from breast cancer.

We know that stress plays a critical role for women recovering from this illness. Research shows that support groups are helpful from the emotional point of view because they teach women how to handle the stress and face their illness without feeling overwhelmed. They also provide new social networks, show women how to control pain and anxiety and use the health care system more efficiently. All of which leads to a better quality of life.

Five out of 10 studies show that support groups can help women to live longer, and in recent years doctors have started to ask important questions about how emotional support relates to the progression of disease.

Our study at Stanford University School of Medicine showed the first association between support groups and survival, and we are trying to expand on these findings now.

Beginning in the mid-1990s, more women than ever were surviving breast cancer thanks to new hormonal approaches and a new generation of chemotherapy and radiotherapy. But women now get far more psychosocial support. At the moment, we're trying to determine if support groups affect how long a breast cancer patient lives.

In the meantime, I tell my patients, "Why not take advantage of these groups? It's a good idea to learn how to handle stress because overall your life will be better. If we can prove that you're also helping your body fight the cancer, that will be icing on the cake."

The physiology of stress

A hopeful sign is that we are beginning to understand several physiological pathways that relate to the management of stress.

One pathway involves cortisol, a hormone released by the adrenal gland that is responsible for the "fight or flight" response that prepares us to either stand and fight or run from a threatening situation. This substance spikes when you need to mobilize your energy. That's why cortisol is typically high when you first wake up in morning, but it should not stay high throughout the day.

At Stanford, we have been looking at women who have high cortisol levels at the wrong time and who also seem to have more rapid progression of breast cancer.

Animal studies have also shown that cortisol disruption results in more rapid tumor growth. It could be that a high cortisol level triggers tumor growth. Another possibility is that cortisol starves normal cells but feeds tumor cells. While we need to know more about the mechanism, our clinical report in the Journal of the National Cancer Institute and review in Brain, Behavior and Immunity shows that high cortisol is a prognostic indicator for breast cancer

We are now engaged in a major follow-up study funded by the National Institutes of Health to learn what happens in the body to de-regulate the usual cortisol pattern. Women in the Bay Area who are interested in participating in this trial, can click here for more information, or call 650-723-3430.

Another major physical pathway to consider is the immune system. While cancer is not solely an immunosuppressive disease, Natural Killer (NK) cells are involved in its surveillance. NK cells attack the cancer cells and their number decreases when the cortisol pattern is disrupted. Stress also impairs NK cell function, not just in cancer patients, but in the normal populace as well. Thus an irregular cortisol pattern may be inhibiting a part of the immune system that helps fight cancer.

Studies on shift work show that women who work all night are more likely to develop breast cancer. Disruption of cortisol patterns may be one explanation.

Another may be a change in melatonin which is produced by the pineal gland. Melatonin levels are high at night, but only when our sleeping patterns are normal. Melatonin has been successfully used as a drug to treat jet lag, but it's also an antioxidant and may serve as a free radical scavenger that prevents DNA damage. It could affect a woman's risk of breast cancer, but more research is needed before we can be sure.

At Stanford, we are now trying to find out if poor sleep — or circadian disruption — is a factor in who gets breast cancer and if so, what can be done about it. Depressed people, for example, usually wake up early in the morning and have trouble getting back to sleep. These people not only have a higher risk of getting cancer, their cancer tends to progress more rapidly, so this is a fertile area for research. We hope to have results within the next two years. Then we will be able to consider whether drugs that would help women sleep better, might help to reduce their risk of breast cancer.

Techniques for reducing stress

Yoga, progressive muscle relaxation and deep breathing are just some of the methods to reduce stress. Self-hypnosis can also reduce anxiety and pain. There is less evidence, but a lot of interesting information on Mindfulness Meditation training as a means of calming both the body and the mind.

We tend to think of the mind-body connection only in a negative sense. If you are anxious and your chest feels tight, and your heart rate goes up, we say that's a "mind-body effect." But the other side of the coin is that people can use this connection to produce relaxation and find a sense of comfort in their bodies.

Relaxation techniques may differ, but the results tend to be the same: People can control their physiological responses. This is all being studied at The National Center for Complementary and Alternative Medicine (NCCAM) at the National Institutes of Health.

The American public has a tremendous appetite for these treatments because CAM practitioners often give patients more time and attention than traditional health care professionals. The average CAM practitioner spends 30 minutes with a patient, the average doctor, 7 minutes.

Americans now spend more for CAM treatments than for primary care, and make more visits to CAM practitioners than they do to the doctor's office, even though we now have less invasive treatments and more effective medications.

There's another compelling reason for the increasing popularity of CAM treatments. You have two problems when you have a disease: First you have to deal with what's going on in your body, and then you have to live with the stress that goes along with it. CAM treatments address chronic pain and anxiety — two things we don't handle well in modern medicine.

The National Center is there to evaluate the new research, and also because people know they need something more than what they receive from modern medicine.

These techniques empower patients and make them equal partners in their own health care. One of the things I feel proudest of is this: if you ask the women in our groups at Stanford, "What was most helpful to you?" they say, "One another."

We have also created support groups on the Internet and found that women can be helped very effectively in this venue. They come to understand that cancer isn't just a meaningless tragedy but an occasion to change their lives and change the lives of others for the better.

For more information about Breast Cancer support groups, contact The National Alliance of Breast Cancer Organizations

General References

Lieberman MA, Golant M, Giese-Davis J, Winzlenberg A, Benjamin H, Humphreys K, Kronenwetter C, Russo S, Spiegel D. "Electronic support groups for breast carcinoma: a clinical trial of effectiveness." Cancer. 2003 Feb 15;97(4):920-5. Abstract

Sephton,S. and D. Speigel, "Circadian Disruption in Cancer: Aneuroendocrine-Immun Pathway from Stress to Disease?" Brain Behavior and Immunity. 2003 17: 321-328. Abstract

Spiegel,D. and K. Giese-Davis. "Depression and Cancer: Mechanisms and Disease Progression," Biological Psychiatry. 2003 54: 269-282.  Abstract

Spiegel, D. Effects of psychotherapy on cancer survival, Nature Reviews Cancer. 2002 2:383 -388. Abstract