Women who suffer from psychological stress are not at risk of getting breast cancer. Although a large majority of women blame mental stress for breast cancer, scientifically there is no association between the two. Recently, evidence gathered by Dr Minouk J Schoemaker and her team at the Institute of Cancer Research in London, shows stress lasting up to five years or stress caused by traumatic life events even in childhood or adolescence, are in no way responsible for causing the cancer.
“Our study has analyzed very large amounts of data from women over many years, and has provided good evidence that stress is unlikely to increase the risk of developing breast cancer,” said Dr Schoemaker.
Breast cancer, abnormal growth of cancerous cells in breasts , is the second most common type of cancer in US women. This cancer is also the most common type of cancer from which women suffer in the world. According to the American Cancer Society (ACS), more than 246,660 new cases of invasive breast cancer will be found in 2016, which will lead to more than 40,450 deaths.
The research dubbed as the Generations Study was carried out to investigate whether stress affects breast cancer risk. Schoemaker and her colleagues evaluated 106,000 women, and after enrollment the women were followed for a period of six years, during which time 1,783 of them developed this cancer.
The cases were evaluated on the basis of how often the women experienced stress and if they had experienced stressful events in their lifetime or in the last five years. The stressful events were classified on the basis of loss of family, getting divorced or personal injury and classified into eight types of stressful events. The research found 74% of the women experienced stress but there was no association between seven of the stressful life events and getting this cancer. While a weak link between estrogen levels and divorce was found in only 25 cases, it was also believed to bear no significance.
Data was also collected on other risk factors of breast cancer including family history, obesity, alcohol consumption, physical activity, number of children, duration of breast feeding etc. The study did highlight women who had lost their mothers to breast cancer were at an increased genetic inclination to develop the same. The research was originally founded to follow the enrolled women for a period of 40 years and the surveillance will continue along with updates on lifestyle information for the participants.
Breast cancer is believed to be caused by a variety of risk factors but they can be categories into two main categories. One type of breast cancer risks include those that cannot be changed or avoided such as lifestyles changes e.g., smoking, drinking, and diet etc, while the other type include non-changeable factors like gender, genetics, aging etc.
Especially the types of breast cancer caused by certain genes i.e., 5-10% of all breast cancer cases can be really severe, since they arise due to gene mutations or defects. Women with an inclination of mutation in genes such as BRCA1, BRCA2, ATM, TP53, CHEK2, PTEN, CDH1, STK11 and PALB2 are at a greater inclination to develop this cancer.
The BRCA1 and BRCA2 gene defect is an inherited mutation. Normally these two genes prevent the formation of cancerous cells inside the breast tissues but in their mutated forms, they do not stop abnormal growths which ultimately lead to cancer. Some women with a BRCA1 mutation have an 80% greater risk of developing cancer while women with BRCA2 mutations have a 45% increased risk. There is a greater inclination of other female related cancers such as ovarian cancers to occur in such women.
Likewise, the ATM gene is responsible for repairing damaged DNA but inheriting at least one abnormal form of the gene has been implicated with a high rate of breast cancer. The gene TP53 is responsible for regulating the synthesis of a p53 protein which helps in stopping the growth of abnormal cells. People with an abnormal form of this gene are generally considered to have the Li-Fraumeni syndrome, in which a person has greater inclination of developing breast cancer, but only in rare cases.
Similarly, the CHEK2 gene can increase the risk breast cancer formation by two-folds, while the PTEN gene mutation can lead cancerous formations i.e., tumors in the breast tissues. The CDH1 mutation can cause a form of hereditary diffuse gastric cancer and women with this defect are at an increased risk of getting invasive lobular breast cancer. The STK11 and PALB2 gene defects are also known for increasing risk of breast cancer but their exact cancer mechanism is not known.
Usually 8 out of 10 women who have breast cancer do not have a family history of the breast cancer, but having a mother, sister or a daughter diagnosed with breast cancer doubly increases the chance, while having two close relations with breast cancer increases the chance by three-folds.