National Breast Cancer Awareness Month has been a great month for solidarity around a major health problem that affects someone that you know. NFL football players in pink shoes, Delta Airline personnel in pink trimmed uniforms, corporate sponsored support and celebrations of scientific advances and personal survival.
When I see a survivor in the ER, often patients are experiencing side effects of therapy: profound weakness, intractable nausea, vomiting and dehydration. Patients sometimes are focused on getting through a single day, feeling miserable despite the love and presence of family members and friends. Survivors struggling with concerns about the uncertainty of the disease, the abrupt change in day to day life, job security, finances and the "I don't want to be a bother to anyone" factor. Often survivors are balancing and juggling life and are stressed prior to their diagnosis.
So let's put the question on the table: "Does stress cause cancer?" Despite the myths; let me be clear. A direct relationship between psychological stress and development of cancer has not been scientifically proven. Research suggests that psychological factors may affect cancer progression (increase in tumor size or spread of the cancer in patients who have cancer).
Here are the details. There is a complex relationship between stress and any health problem.
For many reasons cancer probably has the most complex relationship with stress. First, let's define cancer. Cancer is a problem of uncontrolled cell growth, cells growing much faster than they should. Your genes, your unique genetic makeup (hard wiring) given to you by your parents through proteins regulate and control cell growth in good times and when cancer occurs. Cancer often begins with activation of genes that get "turned on" by a variety of single or multiple factors. These special genes that turn on the unregulated growth cells leading to cancer are called oncogenes. This is an oversimplification of just one path to cancer.
Research examining regulation of cell growth with animal models (animals with a disease that is similar to or the same as a disease in humans) suggests that the body's neuroendocrine response (release of hormones into the blood in response to stimulation of the nervous system) can directly alter important processes in cells that help protect against the formation of cancer, such as DNA repair and the regulation of cell growth.
Triggers of deregulated growth of cells leading to cancers in humans include viruses, radiation, carcinogens, toxins and carcinogenic foods.
What about stress, the immune system and risk of cancer?
The immune system is key for the early stage of cancer growth. Chronic stress weakens the immune system or alters cell processes that could protect against cancer. The classic defenses of the immune system are complex. But consider one type of cell called the natural killer cell and factors such as tumor necrosis factor. Evidence from both animal and human studies suggests that chronic stress weakens a person's immune system, which in turn may affect the incidence of virus-associated cancers, such as Kaposi sarcoma and some lymphoma. Here is a key point. If a weakened immune system alone was the critical factor in causing stress more patients with AIDS (patients with almost no functioning immune system) would have cancer. The fact is that only a select group of AIDS patients have cancer.
It is difficult to separate stress from other physical or emotional factors when examining cancer risk. For example, certain behaviors, such as smoking and using alcohol, and biological factors, such as growing older, becoming overweight and having a family history of cancer are common risk factors for cancer. Researchers may have difficulty controlling the presence of these factors in the study group or separating the effects of stress from the effects of these other factors. In some cases, the number of people in the study, length of follow-up, or analysis used is insufficient to rule out the role of chance. Also, studies may not always take into account that cancer is not a homogeneous (uniform in nature) disease.
How does stress affect people who have cancer -- cancer survivors?
Studies have indicated that stress can affect tumor growth and spread, but the precise biological mechanisms underlying these effects are not well understood. Psychological factors such as helplessness/hopelessness/pessimism tend to lead to poorer prognoses. A new study that is getting lots of attention found that "psychological stress may play a role in the development of aggressive breast cancer, especially among minority populations." This study showed that after diagnosis, black and Hispanic breast cancer patients reported higher levels of stress than whites, and that stress was associated with tumor aggressiveness.
Can reducing stress improve quality of life for breast cancer survivors?
Yes. Cancer support groups have definitively been shown to improve quality of life in breast cancer survivors. The question of prolongation of life depends more on the aggressiveness of the tumor in a particular patient. The pioneer in this area is Stanford University researcher David Spiegel, M.D. Stress and social involvement has been associated with breast cancer survival. According to Spiegel, it remains "very clear" that support groups provide great benefits to cancer patients and should be an important part of treatment. "I've never told my patients to join a support group because it makes you live longer -- I've said to do it because it helps you to live better," he said.
What can you do to transform Breast Cancer Awareness Month into Breast Cancer Action Year Round?
Almost every cancer center has a support group for breast cancer survivors. If you want to make a difference beyond Breast Cancer Awareness Month, discover how you can support a breast cancer survivor support group in your area. If you know a survivor who is struggling with stress, anxiety, depression or hopelessness, please connect them with a support group. Maybe offer to provide a ride or take care of kids to free them to attend.
If you want to learn more about what research has shown to be effective components of a support group visit the site found here and please do visit Stress Relief Radio.com for further insight on the subject from our team.
1) Garssen B. Psychological factors and cancer development: Evidence after 30 years of research. Clinical Psychology Review 2004; 24(3):315-338.
2) Dalton SO, Boesen EH, Ross L, Schapiro IR, Johansen C. Mind and cancer: Do psychological factors cause cancer? European Journal of Cancer 2002; 38(10):1313-1323.