Human Psychology

Cancer is still seen by many as an incurable disease that slowly takes over healthy human tissue, and ultimately causes death. Through advances in medical science, different physical procedures have been developed to treat cancer – for example, chemotherapy, radiotherapy and surgery. In recent years however, there has been a growing perception by cancer specialists and patients that the onset and treatment of cancer may be affected by psychological factors. A new field of research called psycho-oncology has emerged to investigate how the mind can slow down, or even reverse, the progress of cancer. The results from such studies however, have not always been conclusive, and in the case of retrospective studies, have often proved contradictory. While it is important that medical science properly investigate the merit of mind-cancer theories, the benefits of alternative therapies and viewpoints should not be overlooked in the debate over cancer research. The essay briefly surveys the origins of mind-cancer research and the emergence of the field of psycho-oncology, before addressing contemporary research in the area, in particular, the problem of validating results. It concludes by examining the merits of alternative therapies with regard to patient psychology.

Before examining the origins of mind-cancer research, the physiology of cancer will be briefly discussed. "Cancer" is a general term used to describe a physiological disorder in which cells in the body begin to reproduce as abnormal cells, forming a mass called a tumour. There are different types of cancers and tumours, and the body utilises the immune system to destroy the cancerous cells. If the tumour is malignant, the immune system stops the cancer cells from moving to other areas of the body. The immune system halts the spread of the cancer cells by the use of cytotoxic T-cells, also known as "natural killer" (NK) cells. These cells attack the cancerous cells and destroy them. This is why much cancer research over the years has concentrated on the immune system because in effect, this system provides the body's own natural cancer treatment.

In several studies completed over the last two decades, researchers have found that psychological factors such as stress and bereavement can suppress NK cell activity in the body, and the activity of all T-cells in general (Bartrop, 1977; Sali, 1992, cited by Kune, 1992). This phenomenon (immunosuppression) has come to be viewed as a contributing factor in many physiological diseases including allergies, infections, digestive disorders, asthma, heart disease, and cancer (Edelman & Kidman, 1997). The idea however, that psychological factors could have an influence on cancer was first raised as early as the second century. The Greek physician, Galen, noted that depressed women were more likely to develop cancer than happy women (cited by Sdorow, 1995). Other eminent physicians and surgeons also noted that the personalities of people who had developed cancer were markedly different to people who had not developed cancer (cited by Kune, 1992); i.e, they concluded that cancer was more likely to develop in people who possessed a 'melancholy' disposition (cited by Horne, 1996).

This raised the question of why such psychological factors might influence the behaviour of cancer. Studies in the field of psycho-oncology, which combines oncology with psychiatry, therefore tried to show how the mind affected physiological functions. Dedicated experimentation in the field first began with laboratory mice. Sklar and Anisman (1979) implanted cancerous cells into mice, and then subjected them to a series of escapable and inescapable electric shocks. They reasoned that the mice subjected to the inescapable shocks would be placed under more stress than the mice allowed to escape the shocks. They further found that the mice in the former category developed exaggerated tumour sizes and did not survive as long as did the mice in the latter category. Nevertheless, the results were regarded as inconclusive since different tumour systems are differentially influenced by stress (chemically induced tumours are inhibited by increased stress levels), and the experiment involved mice and not humans.

Research was then directed to cancer patients. Many studies concentrated on women suffering from breast cancer, and consisted of interviewing them after a significant event involving their cancer (such as diagnosis, or an operation). The patients were then followed up after a number of years. However, the results often proved contradictory, as has occurred in several retrospective studies. In one well-known case, Ramirez et al. (1989) found that there was a prognostic association between severe life stressors and the recurrence of breast cancer. Barraclough et al. (1992) on the other hand, found that psychosocial adversity such as depression,