The Relationship Between Cancer and the Immune System

Cancer and the Immune System

Addressing this disease is challenging because millions of people have had their lives altered or are privately aware of someone who has had cancer. When initially diagnosed, it is reasonable, justified and rational, to want to know the basis of the problem. After all, cancer prevalence, or those diagnosed and alive with the disease seems high for everyone touched. Expectations of over one and one half million new cancer incidents are the predictions for 2014, and nearly 600,000 Americans die of cancer, almost 1,600 people a day. Cancer accounts for 1 of every 4 deaths of Americans and persists in being the second most frequent cause of death in the US.

The Cancer Stigma

Guilt by h.koppdelaney flickr

Guilt by h.koppdelaney flickr

Historically this illness was highly stigmatized from the belief that a person’s personality style could cause cancer. Even in today’s modern world those with the diagnosis often feel guilty and believe their illness is a sign of weakness. People having these false beliefs, often withhold information or delay treatment further complicating the problem. One of the major barriers to diagnosis and treatment continues to be this stigma or a “what will the neighbors think attitude” that is attached to the cancer diagnosis. Professionals of all types have reduced the stigma of cancer greatly in the past 50 years, but this fear continues to be a barrier that can lead to delayed diagnosis and treatment.

Cancer patients are at high risk for suffering from feelings of guilt or shame, and often have ways of coping that involve avoidance and denial. This is understandable because those diagnosed have to expose themselves to the physical and psychological judgments and treatments of physicians, caregivers, society, friends and family. The word malignant raises alarm in all, and the condition in itself is offensive. Complications of cancer as well as treatments are often disfiguring and even obituaries explain about the “battle” in which the patients lose. People who are sick are afraid of being blamed for developing an illness which is based on how they manage emotions, or because of what they eat, inhale, drink or weigh.

This article is the beginning of a series, and, today I will discuss basic Cancer facts, the immune system response and how this relates to psychological stress. As you read through these pages I would like you to focus on these points: Is there a health psychology relationship? It is possible to combine accurate medical information with health psychology principles to assist in the prevention and treatment of Cancer? I wonder if, society can benefit from utilizing health psychology techniques using a biological, psychological and sociological approach strategy.

What is Cancer?

Cancer is many diseases. The 100 different diseases of cancer are usually named after the cell or organ in which they originate. For example, cancer that begins in the bladder is called bladder cancer, basal cell carcinoma begins in the basal layer of the skin, and the cells are different in each organ. This method of labeling is essentially true for all types of cancers, and treatment methods are specifically targeting the uniqueness of each organ’s cancer cell.

All life forms contain different types of cells. In a specifically controlled manner, cells divide, grow and develop to produce more cells, needed to maintain health. Normally when cells become defective they die and the body regenerates healthy cells. However, sometimes this orderly process is disrupted.

by Ed Uthman flickr Adenocarcinoma on left, normal duct lining on right

by Ed Uthman flickr
Adenocarcinoma on left, normal duct lining on right

Cancer is a condition in which defective or abnormal cells divide out of control. These cells have the ability to infect other tissues, and may invade other parts of the body via blood and lymphatic networks. The cells start out as expected, healthy body-organ cells, but they become damaged or there is a biological mistake made in their normal cell cycle development.

The DNA or genetic materials of a cell can become altered or broken which cause mutations that affect normal division and cell proliferation. The damaged cells continue to divide quickly and begin to accumulate, and change their appearance or mutate. Serving no role in maintaining health, the abnormal cells continue to multiply and grow, sometimes evolving into forming a mass of tissue, which we call a tumor. I would like people to understand, that in every life form, defective cells are routinely produced, and the immune system generally eliminates the altered cells before they cause any physical harm.

How Cancer relates to the Immune system

Cancer was thought to be an immune deficiency disease. In order for someone to develop the disease, the immune system must have been weak which in turn allows the cancer cells to develop, mature, divide and spread. Scientists today believe that the development of cancer is not just the result of a weakened immune system. As cancerous cells divide, they can establish characteristics that hide or defend themselves from the immune system’s recognition. Cancer cells can also mix up the signals between immune cells and send out its own messages to confuse the immune system and prevent it from responding effectively. In other words, cancer cells are very intelligent.

Creative Commons Public Domain

Creative Commons Public Domain

The cells and organs that make up the body’s immune system forms a defense shield against foreign invaders like bacteria, viruses, or something as ordinary as a splinter. The specialized cells of the immune system guard and protect the body like the gladiators of Rome, and respond to invaders by calling for backup from other cells to attack and kill the bacteria or foreign cells. The body’s natural killer cells are called, Macrophages, Dendritic cells, T cells, and Lymphocytes and are specialized cells of the immune system which protect the body from infection.

The immune system has the ability to understand the difference between one of the bodies own cells and a cell of a foreign invader. The immune systems mission is to defend against attacks by foreign cells. However, the problem is that the immune system does not always recognize cancer cells as being foreign invaders. Therefore, cancer as with other diseases may arise when the immune system breaks down and does not function properly in the presence of foreign invaders.

A healthy immune system can easily and efficiently locate foreign cells. When it pertains to cancer, a cell that is dividing abnormally and showing other unusual signs should be identified just like any other foreign cell. In theory, a healthy immune system should destroy cancerous cells before they divide, multiply and overwhelm the organ. We have cancer cells swirling about in our bodies all the time, and yet not everyone develops cancer. When cancer cells do not divide into a tumor, it is because the cells are spread out; clumsy and inefficient, making them easily defeated by a strong, organized, well nourished, and rested army of cells in the immune system. At other times the cancer cells are stronger and more organized than the immune systems’ response cells and they avoid being destroyed.

How the immune system recognizes cancer

The immune system recognizes cancer in a few different ways. Immune cells, called natural killer cells are specialized to find cells that might be infected with a virus, bacteria or pre-cancerous cells because they look sick and the NK cells euthanize them.

The second way that the immune system recognizes cancerous cells is by looking for proteins that should not normally be found on the surface of a healthy cell. Try imagining someone with a cut on their arm that is bleeding, most people would agree that something is wrong because blood is not normally found on the outside of a person unless something is wrong. This is how lymphocytes work, they evaluate the cells of the body and when they see a specific protein that should not be on the surface of a cell, they know that something is wrong and proceed to attack. These killer cells then either send chemical instructions to other immune cells to strip away the cancerous cell or they destroy the invader.

Psychological Stress and the Functioning of the Immune system


Many scientists are studying the role stress in inducing cancer, and there are indeed various conflicting opinions. Psychological stress or anxiety is thought to reduce the body’s immune functions. It has been observed that people are more likely to get sick when they are under stress; like the way college students become ill during the week of final exams. Stress hormones like adrenaline and cortisol have effects on the nervous, endocrine and immune systems of the body. It is thought that adrenaline and cortisol suppress the natural killer cells function and reduce their ability to assess the body for abnormal cells, making people more susceptible to viral infections. Let’s first examine the biological components of cancer and how it relates to stress levels.

Cortisol and Adrenaline is released in response to physical and emotional stress, and appears to reduce immune cell function, which may influence the growth of tumors. Norepinephrine also releases in response to stress along with epinephrine. Norepinephrine has been shown to induce cancerous cell growth in animal model studies. However, this is not proven to relate to humans and other elements of the nervous system exist to protect us from anxiety.

Overall, the studies of how biological responses to stress influence tumor growth provide a vague picture and there is a clear need for further studies to properly evaluate this relationship. For example, one recent study considered the incidence of cancer in women measuring stress levels for five years prior to diagnosis and found no correlation between stress level and the diagnosis of cancer.  Therefore, stress may not directly lead to an increased chance of developing cancer; however, there have been several studies that show that lowered stress levels will at least improve the cancer patients’ quality of life. This area certainly deserves further study.

How stress effects cancer treatment

How many of us have heard or witnessed someone who is ill being told “You’ve got to stay positive, that will help”? This common recommendation is currently under serious scientific scrutiny. The debate about the extent to which psychological processes can directly influence physical health has received significant attention recently.

There is a clear complex relationship between how people view their life experiences, stress levels and illness. Psychological experiences and feelings (stress levels) have a basis in brain chemistry and biology, and it appears that stressful thoughts or perceptions may have at least some influence on our physical health. One clear example is that when people feel anxious, they experience muscle tension, increased heart rate, increased sweating and at times this leads to an increase in blood pressure. Although much more research is needed, there continues to appear to be an association between the body and the mind in terms of maintaining physical health.

quality of life

The strength of the relationship between our thoughts and developing diseases such as cancer cannot yet be determined. However, psychological interventions to reduce negative thinking and to reduce stress and anxiety levels are useful for mental health and improving one’s quality of life.

 Ways to Improve the Immune System

Get plenty of rest: Sleep helps the body reset hormone levels, lowers blood pressure, and allows the body time to heal and repair damages. Restful sleep also helps promote the number of immune cells people have to guard against foreign invaders. (bacteria, viruses)

Wear sunscreen:  UV radiation caused by the sun can cause breaks in the DNA of the body’s cells and these breaks lead to mistakes in cell cycle production that can result in manufacturing precancerous cells. Therefore, it is a good idea to make sunscreen a part of the daily routine.

Maintain a Healthy diet: The foods we consume have extremely powerful effects in the body. Foods containing antioxidants are skilled at removing free radicals from that can arise from substances like UV radiation. If left alone, free radicals can cause DNA damage. This DNA damage can cause an error in cell cycle development and promote precancerous cells. Learning the differences between what to eat and what not to eat is essential for maintaining health.

Vaccinations: When the body encounters a new germ, it can take two to four weeks to launch a strong immune response or attack against this germ. When the immune system recognizes what a germ looks like, it can start mounting an immune response in less than two days, which means people will experience symptoms for a significantly shorter period of time. Vaccines boost the immune system by giving the body a sneak preview or sample of common germs, like the flu virus.

No tobacco or harmful inhalants: Our lungs are a first line of defense against airborne germs. This is called mucosal immunity which includes a whole system of cells and antibodies that clear away inhaled germs from the body. This part of the immune system is suppressed by cigarette smoke and some inhalants’, which makes people more susceptible to infection and injury.


The human body manufactures millions of cells every day, and occasionally for no reason at all a mistake gets made that gives rise to the body producing a precancerous cell. There are usually many questions that arise when cancer has been detected and fortunately, scientists and doctors are making advances in the field of oncology. The more we learn about cancer, the immune system response and how our thoughts and emotions affect physical health the less mysterious and scary cancer will become. There is a health psychology relationship and please visit the library for more information.  I fully believe that it is possible to combine accurate medical information with health psychology techniques to assist in the prevention and treatment of those diagnosed with the illness. In conclusion, patients and society can benefit from utilizing health psychology principles by applying a biological, psychological and sociological approach strategy. Health Psychology for Everyday Lifethe book.

Live Well,

© Dr. Cheryl MacDonald

video of Health Psychology and Therapy

Health Psychology

Cheryl Ann MacDonald, Psy’D.
Health Psychology of San Diego

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Cover Image: canstockphoto|focalpoint

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