Stress and Cancer

Cancer is the name given to the group of diseases that occur when cells in the body grow in an abnormal, uncontrolled way. A group of these growing cells together is called a tumour. Unlike healthy body cells, cancer cells are immortal and can grow forever [1]. Some cancer cells are able to adapt to the medicines used to treat them by becoming resistant to these medicines and this makes treating cancer difficult. In many cases, cancer cells can evolve over time to become more aggressive and are able to spread to other parts of the body (metastasise) where they form new growths.

Metastasis or spreading of cancer involves cells moving away from the growing tumour to other areas of the body. This often occurs by cancer cells entering the blood stream and travelling to other parts of the body like debris drifting on a river. Common areas of the body where cancer can metastasise include the brain and lungs [2,3]. The presence of cancer cells in these organs can stop them from being able to function properly. Because of this, cancer metastasis is the main cause of all cancer-related deaths [4].

Breast cancer is the most common form of cancer diagnosed in Australia; one in seven Australian women is diagnosed with breast cancer in their lifetime [5, 6]. There are 55 Australians newly diagnosed with breast cancer every day [6]. This disease can affect any of the women in our lives – mothers, sisters, daughters, friends, colleagues. Current treatment strategies for breast cancer include surgery to remove the cancerous tissue, as well as chemotherapy to try and kill any dividing cancer cells that may have spread to other parts of the body. Despite improvements in treatment, breast cancer is still the second leading cause of cancer-related death in Australian women [7], so research to improve current treatments and develop new treatments is important.

The treatment of breast cancer in Australia, and the fact that stress has the potential to influence cancer and its consequences, is a complex challenge to address with many interconnected components. Breast cancer comes with an inherent burden to a woman’s physical and mental health, a financial and social impact, as well as a risk of mortality, which all results in substantial stress [10-12]. Stress has associations to quality of life and patient outcome, and emerging evidence suggests stress, both at the systemic and the cellular level, can affect breast cancer metastasis and response to treatment [12-15].

As you can see from the system map above illustrating the issues with treatment of breast cancer in Australia, there are many interlinking problems that need to be addressed. Because there are multiple sources of stress in this system, and since stress can affect cancer metastasis and response to treatment [12-15], there are multiple opportunities for intervention to effect positive change.

At the higher levels of this system, steps by government to

• regulate the costs of pharmaceuticals (reducing financial pressure),
• promote equitable access to treatment through subsidies and
• fund medical research for new and improved treatments

are all key areas where change could translate to significant benefit for someone with breast cancer. At the level of the individual,

• working to provide support,
• encouraging exercise and stress reducing strategies such as mindfulness meditation, as well as
• maintaining a person’s connections and sense of belonging in social, work and community settings

can act to alleviate stressors, improve quality of life and hopefully contribute to improving treatment outcomes.

Further research is needed to properly understand the mechanisms involved in the complex interactions of this problem. Understanding them more completely has the potential to improve the outcome for many cancer patients.