In a U.S. study using mice, researchers discovered that stress biologically reprograms cells from trying to fight the cancer into cells that assist the growth and spread of cancer.
Mice with breast cancer were divided into two groups, with one group confined to a small area for a short period of time every day for two weeks, while the other was not. The growth and spread of cancer was monitored with the stressed group showing cancer cells that moved from the primary tumour and spread to distant parts of the body.
What was interesting, said Steven Cole, associate professor and senior author of the study, was that the primary tumours did not seem to be affected by stress and grew similarly in both groups of mice. However, the stressed animals showed significantly more metastases throughout the body than did the control group. The cancer, in effect, acted differently in the stressed mice.
"This study is not saying that stress causes cancer, but it does show that stress can help support cancer once it has developed," Cole said. "Stress helps the cancer climb over the fence and get out into the big, wide world of the rest of the body."
The study appears in the September 15 peer-reviewed journal Cancer Research. Hopefully, the discovery will also serve as a reminder to the medical community to look at the overall health of the patient, as opposed to the typical focus on the doctor’s area of specialty.