Introduction
Overview
Causes
Factors Related to Fatigue

Cancer treatment Anemia Nutrition factors Psychological factors Mental ability factors Sleep disorders and inactivity Medications

Assessment

Anemia evaluation

Treatment

Psychostimulant drugs Treatment for anemia Exercise Cognitive Behavior Therapy Activity and rest Patient education

Posttreatment Considerations
Get More Information From NCI
Changes to This Summary (12/19/2008)
Questions or Comments About This Summary
About PDQ

Introduction

This patient summary on fatigue is adapted from a summary written for health professionals by cancer experts. This and other credible information about cancer treatment, screening, prevention, supportive care, and ongoing clinical trials is available from the National Cancer Institute. Fatigue is one of the most common complaints of people diagnosed with cancer and cancer survivors. This brief summary describes fatigue, its causes and treatment.

Overview

Fatigue occurs in 14% to 96% of people with cancer, especially those receiving treatment for their cancer. Fatigue is complex, and has biological, psychological, and behavioral causes. Fatigue is difficult to describe and people with cancer may express it in different ways, such as saying they feel tired, weak, exhausted, weary, worn-out, heavy, or slow. Health professionals may use terms such as asthenia, fatigue, lassitude, prostration, exercise intolerance, lack of energy, and weakness to describe fatigue.

Fatigue can be described as a condition that causes distress and decreased ability to function due to a lack of energy. Specific symptoms may be physical, psychological, or emotional. To be treated effectively, fatigue related to cancer and cancer treatment needs to be distinguished from other kinds of fatigue.

Fatigue may be acute or chronic. Acute fatigue is normal tiredness with occasional symptoms that begin quickly and last for a short time. Rest may alleviate fatigue and allow a return to a normal level of functioning in a healthy individual. Chronic fatigue syndrome describes prolonged debilitating fatigue that may persist or relapse, and is not related to cancer. Fatigue related to cancer is called chronic because it lasts over a period of time and is not completely relieved by sleep and rest. Chronic fatigue diagnosed in patients with cancer may be called "cancer fatigue", "cancer-related fatigue", or "cancer treatment-related fatigue". Although many treatment- and disease-related factors may cause fatigue, the exact process of fatigue in people with cancer is not known.

Fatigue can become a very important issue in the life of a person with cancer. It may affect how the person feels about him- or herself, his or her daily activities, family care, and relationships with others, and whether he or she continues with cancer treatment. Patients receiving some cancer treatments may miss work or school, withdraw from friends, need more sleep, and, in some cases, may not be able to think clearly or perform any physical activities because of fatigue. Finances can become difficult if people with fatigue need to take disability leave or stop working completely. Job loss may result in the loss of health insurance or the inability to get medical care. Understanding fatigue and its causes is important in determining effective treatment and in helping people with cancer cope with fatigue. Tests that measure the level of fatigue have been developed.

How long fatigue lasts and how much fatigue the patient feels depends on the type and schedule of cancer treatment. For example, patients treated with cycles of chemotherapy usually have the most fatigue in the days following treatment, then less fatigue until the next treatment. Patients treated with external-beam radiation therapy usually have more fatigue as their treatment continues. It is likely that most patients beginning cancer treatment already feel fatigued following diagnostic tests, surgery, and the emotional distress of coping with a cancer diagnosis.

Causes

Most of the causes of fatigue in patients with cancer are poorly understood, and patients are likely to be coping with many possible causes of fatigue at the same time. Fatigue commonly is an indicator of disease progression and is frequently one of the first symptoms of cancer in both children and adults. For example, parents of a child diagnosed with acute lymphocytic leukemia or non-Hodgkin lymphoma frequently seek medical care because of the child's extreme fatigue. Tumors can cause fatigue directly or indirectly by spreading to the bone marrow, causing anemia, and by forming toxic substances in the body that interfere with normal cell functions. People who are having problems breathing, another symptom of some cancers, may also experience fatigue.

Fatigue can occur for many reasons. The extreme stress that people with cancer experience over a long period of time can cause them to use more energy, leading to fatigue. However, there may be other reasons that patients with cancer suffer from fatigue. The central nervous system (the brain and spinal cord) may be affected by the cancer or the cancer therapy (especially biological therapy) and cause fatigue. Medication to treat pain, depression, vomiting, seizures, and other problems related to cancer may also cause fatigue. Tumor necrosis factor (TNF), a protein made mainly by white blood cells, can cause necrosis (death) of some types of tumor cells and may be given to a patient as a cancer treatment. TNF may cause the loss of protein stores in muscles, making the body work harder to perform normal functions and causing fatigue. There are many chemical, physical, and behavioral factors that are thought to cause fatigue.

Factors Related to Fatigue

It is not always possible to determine the factors that cause fatigue in patients with cancer. Possible factors include the following:

• Cancer treatment.



• Anemia.



• Medications.



• Weight loss and loss of appetite.



• Changes in metabolism.



• Hormone levels that are too low or too high.



• Emotional distress.



• Decline in physical condition.



• Trouble sleeping.



• Inactivity.



• Trouble breathing.



• Loss of strength and muscle coordination.



• Pain and other symptoms.



• High levels of inflammation -causing cytokines.



• Poor nutrition.



• Dehydration.



• Infection.



• Having other medical conditions in addition to cancer.

Fatigue is a common symptom following radiation therapy or chemotherapy. Fatigue may also be a side effect of biologic response modifier therapy, a type of treatment to boost or restore the ability of the immune system to fight cancer, infections, and other diseases. It may be caused by anemia, or the collection of toxic substances produced by cells. In the case of radiation, it may be caused by the increased energy needed to repair damaged skin tissue.

Several factors have been linked with fatigue caused by chemotherapy. Some people may respond to the diagnosis and treatment of cancer with mood changes and disrupted sleep patterns. Nausea, vomiting, chronic pain, and weight loss can also cause fatigue.

Fatigue has long been associated with radiation therapy although the connection between them is not well understood. Fatigue usually lessens after the therapy is completed, but some fatigue may last for months or years following treatment. Patients who are older, have advanced disease, or receive combination therapy (for example, chemotherapy plus radiation therapy) are at a higher risk for developing long-term fatigue.

Biological therapy frequently causes fatigue. In this setting, fatigue is one of a group of side effects known as flu-like syndrome. This syndrome also includes fever, chills, muscle pain, headache, and a sense of generally not feeling well. Some patients may also experience problems with their ability to think clearly. The type of biological therapy used may determine the type and pattern of fatigue experienced.

Many people with cancer undergo surgery for diagnosis or treatment. Fatigue is a problem following surgery, but fatigue from surgery improves with time. It can be made worse, however, when combined with the fatigue caused by other cancer treatments.

Anemia may be a major factor in cancer-related fatigue and quality of life in people with cancer. Anemia may be caused by the cancer, cancer treatment, or may be related to other medical causes.

Fatigue often occurs when the body needs more energy than the amount being supplied from the patient's diet. In people with cancer, 3 major factors may be involved: a change in the body's ability to process food normally, an increased need by the body for energy (due to tumor growth, infection, fever, or problems with breathing), and a decrease in the amount of food eaten (due to lack of appetite, nausea, vomiting, diarrhea, or bowel obstruction).

The moods, beliefs, attitudes, and reactions to stress of people with cancer can contribute to the development of fatigue. Approximately 40% to 60% of the cases of fatigue among all patients (patients with cancer as well as other patients) are not caused by disease or other physical reasons. Anxiety and depression are the most common psychological disorders that cause fatigue.

Depression may be a disabling illness that affects approximately 15% to 25% of people who have cancer. When patients experience depression (loss of interest, difficulty concentrating, mental and physical tiredness, and feelings of hopelessness), the fatigue from physical causes can become worse and last longer than usual, even after the physical causes are gone. Anxiety and fear associated with a cancer diagnosis, as well as its impact on a person's physical, mental, social, and financial well-being are sources of emotional stress. Distress from being diagnosed with cancer may be all that is needed to trigger fatigue. (Refer to the PDQ summaries on Depression ¹ and on Anxiety ² for more information.)

Decreased attention span and difficulty understanding and thinking are often associated with fatigue. Attention problems are common during and after cancer treatment. Attention may be restored by activities that encourage rest. Sleep is also necessary for relieving attention problems but it is not always enough.

Disrupted sleep, poor sleep habits, less sleep at night, sleeping a lot during the day, or no activity during the day may contribute to cancer-related fatigue. Patients who are less active during the daytime and awaken frequently during the night report higher levels of cancer-related fatigue.

Medications other than those used in chemotherapy may also contribute to fatigue. Opioids used in treating cancer-related pain often cause drowsiness, the extent of which may vary depending on the individual. Other types of medications such as tricyclic antidepressants and antihistamines may also produce the side effect of drowsiness. Taking several medications may compound fatigue symptoms.

Assessment

To determine the cause and best treatment for fatigue, the person's fatigue pattern must be determined, and all of the factors causing the fatigue must be identified. The following factors must be included:

1. Fatigue pattern, including how and when it started, how long it has lasted, and its severity, plus any factors that make fatigue worse or better.
2. Type and degree of disease and of treatment-related symptoms and/or side effects.
3. Treatment history.
4. Current medications.
5. Sleep and/or rest patterns and relaxation habits.
6. Eating habits and appetite or weight changes.
7. Effects of fatigue on activities of daily living and lifestyle.
8. Psychological profile, including an evaluation for depression.
9. Complete physical examination that includes evaluation of walking patterns, posture, and joint movements.
10. How well the patient is able to follow the recommended treatment.
11. Job performance.
12. Financial resources.
13. Other factors (for example, anemia, breathing problems, decreased muscle strength).

Underlying factors that contribute to fatigue should be evaluated and treated when possible. Contributing factors include anemia, depression, anxiety, pain, dehydration, nutritional deficiencies, sedating medications, and therapies that may have poorly tolerated side effects. Patients should tell their doctors when they are experiencing fatigue and ask for information about fatigue related to underlying causes and treatment side effects.

There are different kinds of anemia. A medical history, a physical examination, and blood tests may be used to determine the kind and extent of anemia that a person may have. In people with cancer there may be several causes.

Treatment

Most of the treatments for fatigue in cancer patients are for treating symptoms and providing emotional support because the causes of fatigue that are specifically related to cancer have not been determined. Some of these symptom-related treatments may include adjusting the dosages of pain medications, administering red blood cell transfusions or blood cell growth factors, diet supplementation with iron and vitamins, and antidepressants or psychostimulants.

Although fatigue is one of the most common symptoms in cancer, few medications are effective in treating it. A healthcare provider may prescribe medication in low doses that may help patients who are depressed, unresponsive, tired, distracted, or weak. These drugs (psychostimulants) can give a sense of well-being, decrease fatigue, and increase appetite. They are also helpful in reversing the sedating effects of morphine, and they work quickly. However, these drugs can also cause sleeplessness, euphoria, and mood changes. High doses and long-term use may cause loss of appetite, nightmares, sleeplessness, euphoria, paranoid behavior, and possible heart problems.

Treatment for fatigue that is related to anemia may include red blood cell transfusions. Transfusions are an effective treatment for anemia; however possible side effects include infection, immediate transfusion reaction, graft-versus-host disease, and changes in immunity.

Treatment for anemia-related fatigue in patients undergoing chemotherapy may also include drugs, such as epoetin alfa, that cause the bone marrow to make more red blood cells. This type of drug may shorten survival time or may cause some tumors to grow faster. Patients should discuss the risks and benefits ³ of these drugs with their doctors.

Exercise (including light- to moderate-intensity walking programs) helps many people with cancer. People with cancer who exercise may have more physical energy, improved appetite, improved ability to function, improved quality of life, improved outlook, improved sense of well-being, enhanced sense of commitment, and improved ability to meet the challenges of cancer and cancer treatment. Findings from a study of breast cancer survivors suggest that patients may be able to lessen fatigue and pain and function better in daily activities if they take part in moderate to vigorous recreational sports after cancer treatment.

Exercise may also help patients with advanced cancer, even those in hospice care. More benefit may result when family members are involved with the patient in the physical therapy program.

Cognitive behavior therapy (CBT) is a method used by therapists to treat a variety of psychological disorders, including post-cancer treatment fatigue that has no physical cause. CBT aims to change a patient's awareness (the cognitive) in order to change the way he acts (the behavior). CBT sessions may be helpful in decreasing a patient's fatigue following cancer treatment by focusing on factors such as:

• Stress from coping with the experience of having cancer.
• Fear that the cancer may come back.
• Abnormal attitudes about fatigue.
• Irregular sleep or activity patterns.
• Lack of social support.

Any changes in daily routine require the body to use more energy. People with cancer should set priorities and keep a reasonable schedule. Health professionals can help patients by providing information about support services to help with daily activities and responsibilities. An activity and rest program can be developed with a health care professional to make the most of a patient's energy. Practicing sleep habits such as not lying down at times other than for sleep, taking short naps no longer than one hour, and limiting distracting noise (tv, radio) during sleep may improve sleep and allow more activity during the day.

Treating chronic fatigue in patients with cancer means accepting the condition and learning how to cope with it. People with cancer may find that fatigue becomes a chronic disability. Although fatigue is frequently an expected, temporary side effect of treatment, other factors may cause it to continue.

Since fatigue is the most common symptom in people receiving outpatient chemotherapy, patients should learn ways to manage the fatigue. Patients should be taught the following:

• The difference between fatigue and depression



• Possible medical causes of fatigue (not enough fluids, electrolyte imbalance, breathing problems, anemia)



• To observe their rest and activity patterns during the day and over time



• To engage in attention-restoring activities (walking, gardening, bird-watching)



• To recognize fatigue that is a side effect of certain therapies



• To participate in exercise programs that are realistic



• To identify activities which cause fatigue and develop ways to avoid or modify those activities



• To identify environmental or activity changes that may help decrease fatigue



• The importance of eating enough food and drinking enough fluids



• Physical therapy may help with nerve or muscle weakness



• Respiratory therapy may help with breathing problems



• To schedule important daily activities during times of less fatigue, and cancel unimportant activities that cause stress



• To avoid or change a situation that causes stress



• To observe whether treatments being used to help fatigue are working

Posttreatment Considerations

This section is for patients who have had no cancer treatment for at least 6 months. The causes of fatigue are different for patients who are receiving therapy compared to those who have completed therapy. Also, the treatment for fatigue may be different for patients who are no longer receiving treatment for cancer.

Fatigue in people who have completed treatment for cancer and who are considered to be disease-free is a different condition than the fatigue experienced by patients receiving therapy. Fatigue may significantly affect the quality of life of cancer survivors. Studies show that some patients continue to have moderate-to-severe fatigue for up to 18 years after bone marrow transplantation. Long-term therapies such as tamoxifen can also cause fatigue. Fatigue can cause poor school performance years later in children who were treated for brain tumors and cured. Long-term follow-up care is important for patients after cancer therapy. Physical causes should be ruled out when trying to determine the cause of fatigue in cancer survivors.

Get More Information From NCI

Call 1-800-4-CANCER

For more information, U.S. residents may call the National Cancer Institute's (NCI's) Cancer Information Service toll-free at 1-800-4-CANCER (1-800-422-6237) Monday through Friday from 9:00 a.m. to 4:30 p.m. Deaf and hard-of-hearing callers with TTY equipment may call 1-800-332-8615. The call is free and a trained Cancer Information Specialist is available to answer your questions.

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The NCI's LiveHelp® ⁴ online chat service provides Internet users with the ability to chat online with an Information Specialist. The service is available from 9:00 a.m. to 11:00 p.m. Eastern time, Monday through Friday. Information Specialists can help Internet users find information on NCI Web sites and answer questions about cancer.

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Search the NCI Web site

The NCI Web site ⁵ provides online access to information on cancer, clinical trials, and other Web sites and organizations that offer support and resources for cancer patients and their families. For a quick search, use our “Best Bets” search box in the upper right hand corner of each Web page. The results that are most closely related to your search term will be listed as Best Bets at the top of the list of search results.

There are also many other places to get materials and information about cancer treatment and services. Hospitals in your area may have information about local and regional agencies that have information on finances, getting to and from treatment, receiving care at home, and dealing with problems related to cancer treatment.

Find Publications

The NCI has booklets and other materials for patients, health professionals, and the public. These publications discuss types of cancer, methods of cancer treatment, coping with cancer, and clinical trials. Some publications provide information on tests for cancer, cancer causes and prevention, cancer statistics, and NCI research activities. NCI materials on these and other topics may be ordered online or printed directly from the NCI Publications Locator ⁶. These materials can also be ordered by telephone from the Cancer Information Service toll-free at 1-800-4-CANCER (1-800-422-6237), TTY at 1-800-332-8615.

Changes to This Summary (12/19/2008)

The PDQ cancer information summaries are reviewed regularly and updated as new information becomes available. This section describes the latest changes made to this summary as of the date above.

Changes were made to this summary to match those made to the health professional version.

Questions or Comments About This Summary

If you have questions or comments about this summary, please send them to Cancer.gov through the Web site’s Contact Form ⁷. We can respond only to email messages written in English.

About PDQ

PDQ is a comprehensive cancer database available on NCI's Web site.

PDQ is the National Cancer Institute's (NCI's) comprehensive cancer information database. Most of the information contained in PDQ is available online at NCI's Web site ⁵. PDQ is provided as a service of the NCI. The NCI is part of the National Institutes of Health, the federal government's focal point for biomedical research.

PDQ contains cancer information summaries.

The PDQ database contains summaries of the latest published information on cancer prevention, detection, genetics, treatment, supportive care, and complementary and alternative medicine. Most summaries are available in two versions. The health professional versions provide detailed information written in technical language. The patient versions are written in easy-to-understand, nontechnical language. Both versions provide current and accurate cancer information.

The PDQ cancer information summaries are developed by cancer experts and reviewed regularly.

Editorial Boards made up of experts in oncology and related specialties are responsible for writing and maintaining the cancer information summaries. The summaries are reviewed regularly and changes are made as new information becomes available. The date on each summary ("Date Last Modified") indicates the time of the most recent change.

PDQ also contains information on clinical trials.

A clinical trial is a study to answer a scientific question, such as whether one method of treating symptoms is better than another. Trials are based on past studies and what has been learned in the laboratory. Each trial answers certain scientific questions in order to find new and better ways to help cancer patients. Some patients have symptoms caused by cancer treatment or by the cancer itself. During supportive care clinical trials, information is collected about how well new ways to treat symptoms of cancer work. The trials also study side effects of treatment and problems that come up during or after treatment. If a clinical trial shows that a new treatment is better than one currently being used, the new treatment may become "standard." Patients who have symptoms related to cancer treatment may want to think about taking part in a clinical trial.

Listings of clinical trials are included in PDQ and are available online at NCI's Web site ⁸. Descriptions of the trials are available in health professional and patient versions. Many cancer doctors who take part in clinical trials are also listed in PDQ. For more information, call the Cancer Information Service 1-800-4-CANCER (1-800-422-6237); TTY at 1-800-332-8615.

Glossary Terms

The tasks of everyday life. These activities include eating, dressing, getting into or out of a bed or chair, taking a bath or shower, and using the toilet. Instrumental activities of daily living are activities related to independent living and include preparing meals, managing money, shopping, doing housework, and using a telephone. Also called ADL.

Symptoms or signs that begin and worsen quickly; not chronic.

An aggressive (fast-growing) type of leukemia (blood cancer) in which too many lymphoblasts (immature white blood cells) are found in the bone marrow and blood. Also called acute lymphoblastic leukemia and ALL.

Cancer that has spread to other places in the body and usually cannot be cured or controlled with treatment.

A condition in which the number of red blood cells is below normal.

A drug used to treat depression.

A type of drug that blocks the action of histamines, which can cause fever, itching, sneezing, a runny nose, and watery eyes. Antihistamines are used to prevent fevers in patients receiving blood transfusions and to treat allergies, coughs, and colds.

Feelings of fear, dread, and uneasiness that may occur as a reaction to stress. A person with anxiety may sweat, feel restless and tense, and have a rapid heart beat. Extreme anxiety that happens often over time may be a sign of an anxiety disorder.

A desire to satisfy a physical or mental need, such as for food, sex, or adventure.

Weakness; lack of energy and strength.

Pertaining to biology or to life and living things. In medicine, refers to a substance made from a living organism or its products. Biologicals may be used to prevent, diagnose, treat or relieve of symptoms of a disease. For example, antibodies, interleukins, and vaccines are biologicals. Biological also refers to parents and children who are related by blood.

Treatment to boost or restore the ability of the immune system to fight cancer, infections, and other diseases. Also used to lessen certain side effects that may be caused by some cancer treatments. Agents used in biological response modifier therapy include monoclonal antibodies, growth factors, and vaccines. These agents may also have a direct antitumor effect. Also called biological therapy, biotherapy, BRM therapy, and immunotherapy.

Treatment to boost or restore the ability of the immune system to fight cancer, infections, and other diseases. Also used to lessen certain side effects that may be caused by some cancer treatments. Agents used in biological therapy include monoclonal antibodies, growth factors, and vaccines. These agents may also have a direct antitumor effect. Also called biological response modifier therapy, biotherapy, BRM therapy, and immunotherapy.

A tissue with red blood cells, white blood cells, platelets, and other substances suspended in fluid called plasma. Blood takes oxygen and nutrients to the tissues, and carries away wastes.

The soft, sponge-like tissue in the center of most bones. It produces white blood cells, red blood cells, and platelets.

A procedure to replace bone marrow that has been destroyed by treatment with high doses of anticancer drugs or radiation. Transplantation may be autologous (an individual's own marrow saved before treatment), allogeneic (marrow donated by someone else), or syngeneic (marrow donated by an identical twin).

The long, tube-shaped organ in the abdomen that completes the process of digestion. The bowel has two parts, the small bowel and the large bowel. Also called intestine.

The growth of abnormal cells in the tissues of the brain. Brain tumors can be benign (non-cancerous) or malignant (cancerous).

Cancer that forms in tissues of the breast, usually the ducts (tubes that carry milk to the nipple) and lobules (glands that make milk). It occurs in both men and women, although male breast cancer is rare.

A term for diseases in which abnormal cells divide without control. Cancer cells can invade nearby tissues and can spread to other parts of the body through the blood and lymph systems. There are several main types of cancer. Carcinoma is cancer that begins in the skin or in tissues that line or cover internal organs. Sarcoma is cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue. Leukemia is cancer that starts in blood-forming tissue such as the bone marrow, and causes large numbers of abnormal blood cells to be produced and enter the blood. Lymphoma and multiple myeloma are cancers that begin in the cells of the immune system. Central nervous system cancers are cancers that begin in the tissues of the brain and spinal cord.

The individual unit that makes up the tissues of the body. All living things are made up of one or more cells.

The brain and spinal cord. Also called CNS.

Treatment with drugs that kill cancer cells.

A disease or condition that persists or progresses over a long period of time.

A condition lasting for more than 6 months in which a person feels tired most of the time and may have trouble concentrating and carrying out daily activities. Other symptoms include sore throat, fever, muscle weakness, headache, and joint pain.

Pain that can range from mild to severe, and persists or progresses over a long period of time.

A type of research study that tests how well new medical approaches work in people. These studies test new methods of screening, prevention, diagnosis, or treatment of a disease. Also called clinical study.

To adjust to new situations and overcome problems.

To heal or restore health; a treatment to restore health.

A substance that is made by cells of the immune system. Some cytokines can boost the immune response and others can suppress it. Cytokines can also be made in the laboratory by recombinant DNA technology and used in the treatment of various diseases, including cancer.

A condition caused by the loss of too much water from the body. Severe diarrhea or vomiting can cause dehydration.

A mental condition marked by ongoing feelings of sadness, despair, loss of energy, and difficulty dealing with normal daily life. Other symptoms of depression include feelings of worthlessness and hopelessness, loss of pleasure in activities, changes in eating or sleeping habits, and thoughts of death or suicide. Depression can affect anyone, and can be successfully treated. Depression affects 15-25% of cancer patients.

The process of identifying a disease, such as cancer, from its signs and symptoms.

A method used to identify a disease.

Frequent and watery bowel movements.

The things a person eats and drinks.

Cancer that continues to grow or spread.

In medicine, a disturbance of normal functioning of the mind or body. Disorders may be caused by genetic factors, disease, or trauma.

Extreme mental or physical pain or suffering.

The amount of medicine taken, or radiation given, at one time.

Any substance, other than food, that is used to prevent, diagnose, treat or relieve symptoms of a disease or abnormal condition. Also refers to a substance that alters mood or body function, or that can be habit-forming or addictive, especially a narcotic.

A substance that breaks up into ions (particles with electrical charges) when it is dissolved in water or body fluids. Some examples of ions are sodium, potassium, calcium, chloride, and phosphate. These ions help move nutrients into cells, help move waste out of cells, and help nerves, muscles, the heart, and the brain work the way they should.

A substance that is made in the laboratory and stimulates the bone marrow to make red blood cells. It is a type of antianemic and a type of recombinant human erythropoietin.

A feeling of great happiness or well-being. Euphoria may be a side effect of certain drugs.

A type of radiation therapy that uses a machine to aim high-energy rays at the cancer from outside of the body. Also called external radiation therapy.

A condition marked by extreme tiredness and inability to function due lack of energy. Fatigue may be acute or chronic.

An increase in body temperature above normal (98.6 degrees F), usually caused by disease.

Liquid.

Monitoring a person's health over time after treatment. This includes keeping track of the health of people who participate in a clinical study or clinical trial for a period of time, both during the study and after the study ends.

A disease caused when cells from a donated stem cell graft attack the normal tissue of the transplant patient. Symptoms include jaundice, skin rash or blisters, a dry mouth, or dry eyes. Also called GVHD.

A substance made by the body that functions to regulate cell division and cell survival. Some growth factors are also produced in the laboratory and used in biological therapy.

One of many chemicals made by glands in the body. Hormones circulate in the bloodstream and control the actions of certain cells or organs. Some hormones can also be made in the laboratory.

A program that provides special care for people who are near the end of life and for their families, either at home, in freestanding facilities, or within hospitals.

The complex group of organs and cells that defends the body against infections and other diseases.

The condition of being protected against an infectious disease. Immunity can be caused by a vaccine, previous infection with the same agent, or by transfer of immune substances from another person or animal.

Invasion and multiplication of germs in the body. Infections can occur in any part of the body and can spread throughout the body. The germs may be bacteria, viruses, yeast, or fungi. They can cause a fever and other problems, depending on where the infection occurs. When the body’s natural defense system is strong, it can often fight the germs and prevent infection. Some cancer treatments can weaken the natural defense system.

Redness, swelling, pain, and/or a feeling of heat in an area of the body. This is a protective reaction to injury, disease, or irritation of the tissues.

An important mineral the body needs to make hemoglobin, a substance in the blood that carries oxygen from the lungs to tissues throughout the body. Iron is also an important part of many other proteins and enzymes needed by the body for normal growth and development. It is found in red meat, fish, poultry, lentils, beans, and foods with iron added, such as cereal.

In medicine, the place where two or more bones are connected. Examples include the shoulder, elbow, knee, and jaw.

A feeling of tiredness, weakness, and lack of interest in daily activities.

A legal drug that is used to prevent, treat, or relieve symptoms of a disease or abnormal condition.

The total of all chemical changes that take place in a cell or an organism. These changes make energy and the materials needed for growth, reproduction, and maintaining health. They also help get rid of toxic substances.

A narcotic drug used in the treatment of pain.

The National Cancer Institute, part of the National Institutes of Health of the United States Department of Health and Human Services, is the Federal Government's principal agency for cancer research. The National Cancer Institute conducts, coordinates, and funds cancer research, training, health information dissemination, and other programs with respect to the cause, diagnosis, prevention, and treatment of cancer. Access the National Cancer Institute Web site at http://www.cancer.gov. Also called NCI.

A feeling of sickness or discomfort in the stomach that may come with an urge to vomit. Nausea is a side effect of some types of cancer therapy.

Refers to the death of living tissues.

A bundle of fibers that receives and sends messages between the body and the brain. The messages are sent by chemical and electrical changes in the cells that make up the nerves.

Any of a large group of cancers of the immune system. Non-Hodgkin lymphomas can occur at any age and are often marked by enlarged lymph nodes, fever, and weight loss. There are many different types of non-Hodgkin lymphomas which can be divided into aggressive (fast-growing) and indolent (slow-growing) types and can be classified as either B-cell or T-cell non-Hodgkin lymphoma. B-cell non-Hodgkin lymphomas include Burkitt lymphoma, diffuse large B-cell lymphoma, follicular lymphoma, immunoblastic large cell lymphoma, precursor B-lymphoblastic lymphoma, and mantle cell lymphoma. T-cell non-Hodgkin lymphomas include mycosis fungoides, anaplastic large cell lymphoma, and precursor T-lymphoblastic lymphoma. Lymphomas related to lymphoproliferative disorders following bone marrow or stem cell transplantation are usually B-cell non-Hodgkin lymphomas. Prognosis and treatment depend on the stage and type of disease. Also called NHL.

The taking in and use of food and other nourishing material by the body. Nutrition is a 3-part process. First, food or drink is consumed. Second, the body breaks down the food or drink into nutrients. Third, the nutrients travel through the bloodstream to different parts of the body where they are used as "fuel" and for many other purposes. To give the body proper nutrition, a person has to eat and drink enough of the foods that contain key nutrients.

Blockage of a passageway.

A drug used to treat moderate to severe pain. Opioids are similar to opiates such as morphine and codeine, but they do not contain and are not made from opium.

A patient who visits a health care facility for diagnosis or treatment without spending the night. Sometimes called a day patient.

A mental disorder in which a person has an extreme fear and distrust of others. A paranoid person may have delusions that people are trying to harm him or her.

PDQ is an online database developed and maintained by the National Cancer Institute. Designed to make the most current, credible, and accurate cancer information available to health professionals and the public, PDQ contains peer-reviewed summaries on cancer treatment, screening, prevention, genetics, complementary and alternative medicine, and supportive care; a registry of cancer clinical trials from around the world; and directories of physicians, professionals who provide genetics services, and organizations that provide cancer care. Most of this information, and more specific information about PDQ, can be found on the NCI's Web site at http://www.cancer.gov/cancertopics/pdq. Also called Physician Data Query.

An exam of the body to check for general signs of disease.

The use of exercises and physical activities to help condition muscles and restore strength and movement. For example, physical therapy can be used to restore arm and shoulder movement and build back strength after breast cancer surgery.

In medicine, action taken to decrease the chance of getting a disease or condition. For example, cancer prevention includes avoiding risk factors (such as smoking, obesity, lack of exercise, and radiation exposure) and increasing protective factors (such as getting regular physical activity, staying at a healthy weight, and having a healthy diet).

A condition in which a person is so tired or weak that he or she is unable to do anything.

A molecule made up of amino acids that are needed for the body to function properly. Proteins are the basis of body structures such as skin and hair and of substances such as enzymes, cytokines, and antibodies.

Having to do with how the mind works and how thoughts and feelings affect behavior.

A drug that causes a sense of well-being, decreases fatigue and depression, and increases the desire to eat. These drugs can also cause mood changes and trouble with sleeping.

The overall enjoyment of life. Many clinical trials assess the effects of cancer and its treatment on the quality of life. These studies measure aspects of an individual’s sense of well-being and ability to carry out various activities.

Energy released in the form of particle or electromagnetic waves. Common sources of radiation include radon gas, cosmic rays from outer space, medical x-rays, and energy given off by a radioisotope (unstable form of a chemical element that releases radiation as it breaks down and becomes more stable).

The use of high-energy radiation from x-rays, gamma rays, neutrons, protons, and other sources to kill cancer cells and shrink tumors. Radiation may come from a machine outside the body (external-beam radiation therapy), or it may come from radioactive material placed in the body near cancer cells (internal radiation therapy). Systemic radiation therapy uses a radioactive substance, such as a radiolabeled monoclonal antibody, that travels in the blood to tissues throughout the body. Also called irradiation and radiotherapy.

A cell that carries oxygen to all parts of the body. Also called erythrocyte and RBC.

The return of signs and symptoms of cancer after a period of improvement.

Exercises and treatments that help improve or restore lung function.

In clinical trials, the step-by-step plan for how patients are to be treated; for example, the drug or type of radiation therapy that is to be given, the method by which it is to be given, the amount of time between courses, and the total length of treatment.

Checking for disease when there are no symptoms. Since screening may find diseases at an early stage, there may be a better chance of curing the disease. Examples of cancer screening tests are the mammogram (breast), colonoscopy (colon), Pap smear (cervix), and PSA blood level and digital rectal exam (prostate). Screening can also include checking for a person’s risk of developing an inherited disease by doing a genetic test.

A drug or substance used to calm a person down, relieve anxiety, or help a person sleep.

Convulsion; a sudden, involuntary movement of the muscles.

A problem that occurs when treatment affects healthy tissues or organs. Some common side effects of cancer treatment are fatigue, pain, nausea, vomiting, decreased blood cell counts, hair loss, and mouth sores.

A network of family, friends, neighbors, and community members that is available in times of need to give psychological, physical, and financial help.

A column of nerve tissue that runs from the base of the skull down the back. It is surrounded by three protective membranes, and is enclosed within the vertebrae (back bones). The spinal cord and the brain make up the central nervous system, and spinal cord nerves carry most messages between the brain and the rest of the body.

The response of the body to physical, mental, or emotional pressure. This may make a person feel frustrated, angry, or anxious, and may cause unhealthy chemical changes in the body. Untreated, long-term stress may lead to many types of mental and physical health problems.

Adding nutrients to the diet.

Care given to improve the quality of life of patients who have a serious or life-threatening disease. The goal of supportive care is to prevent or treat as early as possible the symptoms of a disease, side effects caused by treatment of a disease, and psychological, social, and spiritual problems related to a disease or its treatment. Also called comfort care, palliative care, and symptom management.

A procedure to remove or repair a part of the body or to find out whether disease is present. An operation.

An indication that a person has a condition or disease. Some examples of symptoms are headache, fever, fatigue, nausea, vomiting, and pain.

A set of symptoms or conditions that occur together and suggest the presence of a certain disease or an increased chance of developing the disease.

A drug used to treat certain types of breast cancer in women and men. It is also used to prevent breast cancer in women who have had ductal carcinoma in situ (abnormal cells in the ducts of the breast) and are at a high risk of developing breast cancer. Tamoxifen is also being studied in the treatment of other types of cancer. It blocks the effects of the hormone estrogen in the breast. Tamoxifen is a type of antiestrogen. Also called Nolvadex and tamoxifen citrate.

Treatment.

A group or layer of cells that work together to perform a specific function.

Having to do with poison or something harmful to the body. Toxic substances usually cause unwanted side effects.

The infusion of components of blood or whole blood into the bloodstream. The blood may be donated from another person, or it may have been taken from the person earlier and stored until needed.

A type of drug used to treat depression.

An abnormal mass of tissue that results when cells divide more than they should or do not die when they should. Tumors may be benign (not cancerous), or malignant (cancerous). Also called neoplasm.

A protein made by white blood cells in response to an antigen (substance that causes the immune system to make a specific immune response) or infection. Tumor necrosis factor can also be made in the laboratory. It may boost a person’s immune response, and also may cause necrosis (cell death) of some types of tumor cells. Tumor necrosis factor is being studied in the treatment of some types of cancer. It is a type of cytokine. Also called TNF.

A nutrient that the body needs in small amounts to function and stay healthy. Sources of vitamins are plant and animal food products and dietary supplements. Some vitamins are made in the human body from food products. Vitamins are either fat-soluble (can dissolve in fats and oils) or water-soluble (can dissolve in water). Excess fat-soluble vitamins are stored in the body’s fatty tissue, but excess water-soluble vitamins are removed in the urine. Examples are vitamin A, vitamin C, and vitamin E.

To eject some or all of the contents of the stomach through the mouth.

Refers to a blood cell that does not contain hemoglobin. White blood cells include lymphocytes, neutrophils, eosinophils, macrophages, and mast cells. These cells are made by bone marrow and help the body fight infections and other diseases. Also called WBC.