The following excerpt is taken from Chapter
of Colon & Rectal Cancer: A Comprehensive Guide for
Patients & Families by Lorraine Johnston, copyright 2000 by
O'Reilly & Associates, Inc. For book orders/information, call
(800) 998-9938. Permission is granted to print and distribute this
excerpt for noncommercial use as long as the above source is
included. The information in this article is meant to educate and
should not be used as an alternative for professional medical care.
Some people believe that their colorectal cancer was caused by
stress, or that it will be made worse by stress, or that perhaps they have a
cancer-prone personality. Many research studies have attempted to discover
links between cancer, stress, depression, personality, and coping skills. The
connections are complex:
- First, there is no consistent evidence that stress causes or worsens
cancer. Studies done using animals and humans do not consistently show a
positive association between stress and cancer, not even when underlying
disease already exists. In fact, in some animals, some forms of stress cause
tumors to shrink. More details are provided later in this chapter, under
"Stress and cancer?"
- Second, the few studies that hint at a link between personality and cancer
are not conclusive for various reasons, such as the design of the study.
Details are discussed in the section entitled "A cancer
personality?", which appears later in this article.
Experts in various fields of medicine and psychology recognize many
different circumstances and events as stressful. Depending on the circumstances
or point of view, stress could be viewed as a threatening object or the event
itself, the physical reaction within our bodies to the threat, or the state of
mind that precedes our taking some action in response to the threat.
To the psychiatrist studying brain chemistry, our awakening in the morning
and the corresponding rise or fall in levels of several hormones may be viewed
as a stressful event for the constantly adapting brain. For the psychologist,
overcrowding of humans in urban areas can be viewed as a stressful event. For
an orthopedic surgeon, the impact sustained by cartilage within the knee when
one runs on concrete is viewed as stress.
The psychoneuroimmunologist, however, views the interaction of the immune
system with the central nervous system as an adaptation to stress. This
interpretation, which can accommodate both physical and emotional stress, will
be the chief focus of this article.
For the sake of readability, we won't differentiate between responses and
reactions, nor between anxiety and worry. We will assume that the stress of a
cancer diagnosis causes distress, although some authorities maintain that not
all stressors cause distress.
Our bodies and minds respond to stress in many ways. These adaptations may
change with the type and intensity of the stressor, with the amount of time we
have been exposed to it, with our previous experiences trying to adapt to
similar stressful events, with the person experiencing stress, and his or her
physical and emotional state at the time.
Although many emotional responses to stress are possible, such as anger and
withdrawal, the responses most often reported by cancer survivors are fear,
anxiety, and depression. The National Cancer Institute reports that during and
after diagnosis and treatment, almost 50 percent of cancer patients report
anxiety and about 25 percent report significant anxiety; 20 percent experience
transient or long-term depression; and 15 percent are diagnosed with
post-traumatic stress disorder. Estimates by other researchers are sometimes
Fear is sometimes useful
Several bodily changes occur as a reaction to a fearful event. During fear,
hormones that prepare us to adapt to stress are released in a chain reaction,
first from the brain, which trigger in turn the release of stress hormones from
the adrenal glands. Our heart rate increases, blood is redirected to body parts
associated with fight or flight, and extra sugar is made available in the
bloodstream via the liver.
Fear can be a useful, goal-oriented reaction to a stressor. Each of these
physical changes is aimed either at our fleeing from danger or conquering it
Fascinating research into brain structure and function has shown that the
amygdala, part of the "old brain" conserved in most creatures from
reptiles up through the primates, including humans, is the brain organ
responsible for finding safety quickly when fear arises. Direct connections
between the amygdala and our sensory organs bypass the higher brain centers of
decision-making, allowing us to react very quickly to threats, sometimes
without our being aware that we have perceived them. For instance, if you hike
in the woods, have you ever stopped abruptly after sensing just a muted change
of color or pattern, and upon closer inspection realize that subtle difference
is a snake? This brain connection is probably responsible for the immediate,
calm, highly effective, goal-oriented behavior that some people exhibit in
unbelievably horrifying situations.
Although fear doesn't feel good, it can be a useful, goal-oriented reaction
to a stressor. It galvanizes us and prepares us for action. The extreme and
immediate physical reaction to fear, however, does little or nothing to prepare
us to deal intellectually with a fearful situation that requires extensive
analysis, planning, and decision-making, such as absorbing the technical
medical information about our cancer diagnosis. On the contrary, research has
shown that both very low and very high levels of the stress hormones from the
adrenal gland interfere with learning new tasks. Short of our ability to jump
up and flee the doctor's office, or our sudden acquisition of strength to
throttle the bearer of bad news, we have been poorly prepared by evolution for
dealing with cancer as a stressful event. As a result, an out-of-phase mismatch
of events is what many of us experience when being told of the cancer
diagnosis--with a strong likelihood that we will remember forever and with
great acuity the perceptual cues that were present, instead of the key points
that the doctor attempted to relay.
Anxiety is unhealthy
Most adults have experienced the difference between fear and anxiety. Fear
is an acute, strong, visceral response to stress. Anxiety is a nagging,
chronic, or generalized fear response. Although some would choose the chronic
physical distress of anxiety over the pronounced physical distress of fear,
anxiety may be the more physically harmful of the two experiences.
Unresolved fear may convert to anxiety as we begin to grow accustomed to a
threat. When we're anxious, the same physical changes that accompany fear occur
at lower levels, with deleterious effects on our body. Sustained increased
heart output and constriction of blood vessels to rechannel blood to certain
organs can contribute to the development of high blood pressure and
cardiovascular disease. Altered sugar metabolism can worsen diabetes. The
tendency for digestive activity to increase in times of stress can exacerbate
underlying gastric ulcers.
Worry and anxiety involve recycling the same fear, repeatedly examining the
outcomes and evaluating interventions. We sometimes use this activity to
justify worry, assuming that repeated scrutiny will result in knowing what to
do if worse comes to worst, but this continual rehearsal of negative events in
search of solutions may not benefit us should danger actually arise. The two
thought processes, worry and planning, center in different parts of the brain.
On magnetic resonance imaging, those who worry show activity in the emotional
part of the brain, whereas those who plan show activity in the opposite
hemisphere, the so-called logical half of the brain. This may mean that, from
the standpoint of providing a good solution in the face of danger, worry is not
the best strategy. Worry does not determine the best solution and move on to
the next problem. It prevents us from detecting and dealing with new problems
in a timely and effective way.
Physical symptoms of anxiety may include any of these: shortness of breath,
sigh breathing, dry mouth, inability to swallow, trembling, weakness, incessant
crying, circular or obsessive thoughts, inability to concentrate, paralytic or
manic movements, insomnia, headache, recurrent nightmares, or extreme
What feels like anxiety is not always caused by worry. Sometimes it can have
physical causes. In some cases, symptoms that are indistinguishable from
anxiety can be caused by the tumor itself:
- Colorectal cancer tumors in the lung can cause shortness of breath.
- Tumors in parts of the kidney can stimulate the adrenal gland to
overproduce cortisol, a hormone released during fearful episodes.
- Tumors of the brain near or in the pituitary can stimulate hormones that in
turn stimulate the adrenals to overproduce cortisol.
These medications also can cause anxiety:
- Corticosteroids such as prednisone
- Bronchodilators and certain other drugs used for asthma
- The newer antidepressant drugs to control nausea and pain, such as
- Cessation of the use of the quick-acting anti-anxiety drugs, such as Valium
Certain physical changes that accompany incipient medical conditions are
heralded by feelings of anxiety:
- Heart attack
- Electrolyte imbalance
But the chief cause of anxiety among cancer survivors is worry and
sustained, unresolved fear. Fear of pain, of abandonment, of dependency; fear
of financial ruin, of professional ruin, of relapse, of death.
The day following the end of treatment, I got what I can only describe as a
feeling of food stuck in my esophagus mid-chest area. For the next 72 hours I
could not keep any food or even sips of water down without promptly vomiting
them back up. I finally called the doctor Monday morning and he suggested I
take Maalox and ordered Compazine suppositories.
I wasn't nauseated at all, and thought, "How is this going to help?"
But after reading the insert that came with the Compazine prescription, I
discovered that it also is good for anxiety. I don't know how exactly it works,
but I guess it relaxed the spasm enough that I was finally able to eat
something and keep it down, for a day anyway.
When we worry for a long time about one problem, new electrical circuitry is
laid in our brains. Sometimes conditions resembling or related to our problem
will trigger anxiety symptoms, or symptoms of physical distress. Many cancer
survivors report anticipatory nausea just smelling the rubbing alcohol used to
clean the skin over a vein before chemotherapy is administered. Studies have
shown that this response can cause their blood counts to drop--even if they are
not given chemotherapy in that session.
Obviously this reaction, called a conditioned response, can have a direct
impact on the immune system, as has been demonstrated many times in animals.
For example, when rats in one experiment were fed a combination of immune
suppressant and saccharine dissolved in water, their white blood cell counts
dropped afterward, as expected. When the experiment was repeated using only
saccharine in water, white blood cell counts still dropped. This demonstrates
that the association of event and outcome does not require knowing, for
example, what chemotherapy is intended to do. Physiological cause and effect
can occur absent the cognitive processes as we know them today.
This does not imply, of course, that you can skip chemotherapy because just
thinking about it may have some of the same effects. There's no evidence that a
conditioned drop in blood counts coincides with an attack by the immune system
on tumor cells.
Research has shown that those who are depressed often have suboptimal immune
Most cases of depression that coincide with cancer are called situational
depressive episodes, directly related to the stress of adjusting to cancer.
These depressive episodes differ from organic disturbances such as manic
depression or unipolar depression, unless the person has had episodes of these
diseases in the past, well before the cancer diagnosis.
Depression may be diagnosed if one or more of the following symptoms persist
for more than two weeks:
- Excessive sleepiness
- Appetite disturbance
- Inability to function
- Loss of interest in sex and other pleasurable activities
- Thoughts of suicide
Cancer-related problems that seem to have no solution can cause depression.
When we experience repeatedly that our efforts to solve problems don't work, or
are punished, we cease trying. Experts call this "learned
helplessness," but we know it as despair, and it is linked to depression.
Subsequently, when new problems arise that we could indeed solve, or when new
methods of dealing with old problems emerge, those exhibiting learned
helplessness fail to act. A therapist trained to deal with depression can help
overcome learned helplessness and despair.
In addition to the psychological factors surrounding cancer that can cause
depression, chemical treatments for cancer that are neurotoxic or toxic to the
thyroid, such as Taxol, prednisone, interferon alfa, or interleukin-2 can cause
chemically induced depression. Please note, though, that these possible side
effects do not necessarily occur in every person.
The stress hormones released by the adrenals during episodes of fear and
anxiety also affect white blood cells, the infection-fighting army within our
blood. Initially, the surge of brain and adrenal hormones that accompanies
stress causes an increase in circulating white blood cells. When cortisol
remains high, however, white blood cell numbers are reduced. As stress,
anxiety, or depression continue unabated over weeks or months, output of the
adrenal hormone cortisol is consistently high and white blood cell numbers
Stress and cancer?
If prolonged stress and resulting anxiety affect the number of white blood
cells in our body, does this mean that cancer can be caused or made worse by
stress? The answer, based on animal and human research, is unclear.
Animal studies support what many recognize intuitively: if stress had an
unequivocal link to the development of cancer, just about every one of us would
develop cancer. If stressful life events within the last three years were
responsible for the emergence of cancer, then everyone who survived
imprisonment in Auschwitz and other Nazi annihilation camps ought to have been
diagnosed with cancer soon after being freed by the Allies. Continuing with the
same analogy, all people who are diagnosed with cancer should either develop a
second cancer triggered by the stress of the first diagnosis, or should never
be able to recover from the first cancer. Likewise, all loved ones of those
diagnosed with cancer should then develop a cancer from dealing with the stress
of their loved ones' suffering.
In fact, animal studies show a very wide range of tumor response to stress,
depending on the type of stressor used, the ability of the animal to modify or
escape the stressor, the species being tested, the gender, the animal's
previous experience with this stress, whether the tumor was chemically induced
or transplanted, whether the tumor is primary or a metastasis, and so on. In
some cases, stress causes animal tumors to shrink.
Human studies to date have been somewhat less direct in measuring stress and
tumor response, because few humans would tolerate having tumors chemically
induced or transplanted, or being deliberately subjected to stress. The best
study design would follow cancer-free people for years, recording stressful
events and subsequent cancer diagnoses.
Most human studies so far have relied on retrospective self-reports of
stress levels prior to the cancer diagnosis. This method of collecting
information is often criticized as of dubious reliability. For instance, a
person who has just been diagnosed with cancer and who has agreed to fill out a
questionnaire on life factors may report that other recent stressful life
events were not very stressful. Compared to this newest problem, cancer, indeed
these events may, in retrospect, seem not to be. Yet at the time the previous
stressful events occurred, they may have been perceived and reacted to as very
In short, while stress has been undeniably linked, over and over, to
increased rates of some illness such as upper respiratory infection and certain
autoimmune disease, there is no clear causative link between stress and
A cancer personality?
If stress causes both emotional and physical changes, but does not
consistently have a part in the development of cancer, what other factors might
be responsible? Can the ways a person adapts to stress affect his or her
health? Do habitual ways of adapting hint at a "cancer personality"?
The evidence, based on animal and human research, is conflicting.
Obviously, animal studies on this topic are difficult to perform because we
can't know with certainty what animals are feeling, so most studies are done on
humans. Often, the design of these studies has been criticized.
For instance, melancholia, or what we would call depression today, received
attention in the past as a personality trait possibly linked to cancer, but we
know today that depression is less a personality trait or coping mechanism than
an imbalance in brain chemistry with many different causes, including genetics,
situational adjustment, influenza, and stroke.
One study of breast cancer survivors assessed personality and coping styles,
using a questionnaire and interview the day before breast biopsy. The study
concluded that women who were stoical and "psychologically morbid"
rather than expressive and emotional were more likely to have malignant
findings in biopsied tissue. Here are some reasons why the design of studies of
this kind are criticized:
- Those of us who have had biopsies know that this is often a stressful
experience, likely to derail our responses, if we are able at all to take such
an interview seriously in this very emotionally charged setting.
- Suppose those found to have a malignancy already had a good idea what their
diagnosis might be? Suppose this idea had time to develop for a week or two
while they waited for the surgery? Would the women questioned be likely to
display more evolved, thought-out, stoical coping styles, perhaps not
consistent with their usual more spontaneous reactions? In fact, some of the
women in this study indeed had been informed by their radiologists that the
lesions appearing on mammography were most likely malignant.
- How can we know that the answers on a questionnaire, even when the anxiety
surrounding a biopsy is not an issue, reflect how someone really behaves?
- Suppose coping styles early in life predispose us to breast cancer, but our
coping styles at maturity are what is measured by these questionnaires?
- What kind of person volunteers to fill out a questionnaire? (Questionnaire
studies always face this criticism.) Would emotional women be more likely to
decline, and stoical women more likely to comply? Or, if a small honorarium is
offered, say about thirty dollars, as is common for many psychological studies,
will less affluent women be over-represented because, for an affluent women,
the invasion of privacy and the time lost isn't worth thirty dollars? If so, do
less affluent women have other life conditions that would predispose them to
breast cancer, such as living in an air-polluted neighborhood?
- Suppose the behavior described as stoical is an artifact of some other
circumstance, such as working long, exhausting hours under artificial light for
several years? Other, equally plausible theories suggest that the increasing
rate of breast cancer is linked to increasing lifetime estrogen exposure.
Studies have demonstrated that estrogen exposure begins earlier now, for the
age of first menstruation has steadily decreased in industrialized countries
since the use of electric light became widespread in the twentieth
- And finally, if this study had been designed in an era when being stoical
was admired, and being expressive was considered "psychologically
morbid," would the researchers have attempted to prove that expressive
women were more likely to develop breast cancer?
In my family, we have had five cancers: one male denier who has survived eight
years, a female outspoken fighter who has died, an emotional, expressive man
who has died, an introverted female who has died, and an outspoken, complaining
female who has survived twenty years. In each case, type of cancer--lymphoma,
colorectal, prostate, and breast cancers--and stage of disease at diagnosis
were far more meaningful to survival than personality type.
No doubt each of us can think of similar cases within our own experience, in
spite of the findings of studies published on this topic. Indeed, some studies
have found no association between personality, coping style, and breast
As you can see, the supposed link between personality and the development of
cancer is a tenuous one.