Introduction
Overview
Diagnosis
Treatment

Treatment with Drugs Treatment with Psychotherapy

Evaluation and Treatment of Suicidal Patients with Cancer

Effects of suicide on family and health care providers

Assisted Dying, Euthanasia, and Decisions Regarding End of Life
Considerations for Depression in Children

Diagnosis of Childhood Depression Treatment of Childhood Depression

Suicide and Children
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 depression 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 online at NCI's Web site ¹. This brief summary describes the causes and treatment of depression, and risk factors and prevention of suicide in adults and children who have cancer.

Overview

Depression is a disabling illness that affects about 15% to 25% of cancer patients. It affects men and women with cancer equally. People who face a diagnosis of cancer will experience different levels of stress and emotional upset. Important issues in the life of any person with cancer may include the following:

• Fear of death.
• Interruption of life plans.
• Changes in body image and self-esteem.
• Changes in social role and lifestyle.
• Money and legal concerns.

Everyone who is diagnosed with cancer will react to these issues in different ways and may not experience serious depression or anxiety.

Patients who are receiving palliative care for cancer may have frequent feelings of depression and anxiety, leading to a much lower quality of life. Patients in palliative care who suffer from depression report being more troubled about their physical symptoms, relationships, and beliefs about life. Depressed terminally ill patients have reported feelings of "being a burden" even when the actual amount of dependence on others is small.

Just as patients need to be evaluated for depression throughout their treatment, so do family caregivers. Caregivers have been found to experience a good deal more anxiety and depression than people who are not caring for patients with cancer. Children are also affected when a parent with cancer develops depression. A study of women with breast cancer showed that children of depressed patients were the most likely to have emotional and behavioral problems themselves.

There are many misconceptions about cancer and how people cope with it, such as the following:

• All people with cancer are depressed.
• Depression in a person with cancer is normal.
• Treatment does not help the depression.
• Everyone with cancer faces suffering and a painful death.

Sadness and grief are normal reactions to the crises faced during cancer, and will be experienced at times by all people. Because sadness is common, it is important to distinguish between normal levels of sadness and depression. An important part of cancer care is the recognition of depression that needs to be treated. Some people may have more trouble adjusting to the diagnosis of cancer than others may. Major depression is not simply sadness or a blue mood. Major depression affects about 25% of patients and has common symptoms that can be diagnosed and treated. Symptoms of depression that are noticed when a patient is diagnosed with cancer may be a sign that the patient had a depression problem before the diagnosis of cancer.

All people will experience reactions of sadness and grief periodically throughout diagnosis, treatment, and survival of cancer. When people find out they have cancer, they often have feelings of disbelief, denial, or despair. They may also experience difficulty sleeping, loss of appetite, anxiety, and a preoccupation with worries about the future. These symptoms and fears usually lessen as a person adjusts to the diagnosis. Signs that a person has adjusted to the diagnosis include an ability to maintain active involvement in daily life activities, and an ability to continue functioning as spouse, parent, employee, or other roles by incorporating treatment into his or her schedule. If the family of a patient diagnosed with cancer is able to express feelings openly and solve problems effectively, both the patient and family members have less depression. Good communication within the family reduces anxiety. A person who cannot adjust to the diagnosis after a long period of time, and who loses interest in usual activities, may be depressed. Mild symptoms of depression can be distressing and may be helped with counseling. Even patients without obvious symptoms of depression may benefit from counseling; however, when symptoms are intense and long-lasting, or when they keep coming back, more intensive treatment is important.

Diagnosis

The symptoms of major depression include the following:

• Having a depressed mood for most of the day and on most days.



• Loss of pleasure and interest in most activities.



• Changes in eating and sleeping habits.



• Nervousness or sluggishness.



• Tiredness.



• Feelings of worthlessness or inappropriate guilt.



• Poor concentration.



• Constant thoughts of death or suicide.

To make a diagnosis of depression, these symptoms should be present on most days for at least 2 weeks. The diagnosis of depression can be difficult to make in people with cancer due to the difficulty of separating the symptoms of depression from the side effects of medications or the symptoms of cancer. This is especially true in patients undergoing active cancer treatment or those with advanced disease. Symptoms of guilt, worthlessness, hopelessness, thoughts of suicide, and loss of pleasure are the most useful in diagnosing depression in people who have cancer.

Some people with cancer may have a higher risk for developing depression. The cause of depression is not known, but the risk factors for developing depression are known. Risk factors may be cancer-related and noncancer-related.

• Cancer-Related Risk Factors:
  • Depression at the time of cancer diagnosis.
  • Poorly controlled pain.
  • An advanced stage of cancer.
  • Increased physical impairment or pain.
  • Pancreatic cancer.
  • Being unmarried and having head and neck cancer.
  • Treatment with some anticancer drugs.



• Noncancer-Related Risk Factors:
  • History of depression.
  • Lack of family support.
  • Other life events that cause stress.
  • Family history of depression or suicide.
  • Previous suicide attempts.
  • History of alcoholism or drug abuse.
  • Having many illnesses at the same time that produce symptoms of depression (such as stroke or heart attack).

The evaluation of depression in people with cancer should include a careful evaluation of the person's thoughts about the illness; medical history; personal or family history of depression or suicide; current mental status; physical status; side effects of treatment and the disease; other stresses in the person's life; and support available to the patient. Thinking of suicide, when it occurs, is frightening for the individual, for the health care worker, and for the family. Suicidal statements may range from an offhand comment resulting from frustration or disgust with a treatment course, such as "If I have to have one more bone marrow aspiration this year, I'll jump out the window," to a statement indicating deep despair and an emergency situation, such as, "I can't stand what this disease is doing to all of us, and I am going to kill myself." Exploring the seriousness of these thoughts is important. If the thoughts of suicide seem to be serious, then the patient should be referred to a psychiatrist or psychologist, and the safety of the patient should be secured.

The most common type of depression in people with cancer is called reactive depression. This shows up as feeling moody and being unable to perform usual activities. The symptoms last longer and are more pronounced than a normal and expected reaction but do not meet the criteria for major depression. When these symptoms greatly interfere with a person's daily activities, such as work, school, shopping, or caring for a household, they should be treated in the same way that major depression is treated (such as crisis intervention, counseling, and medication, especially with drugs that can quickly relieve distressing symptoms). Basing the diagnosis on just these symptoms can be a problem in a person with advanced cancer since the illness may be causing decreased functioning. It is important to identify the difference between fatigue and depression since they can be assessed and treated separately. In more advanced illness, focusing on despair, guilty thoughts, and a total lack of enjoyment of life is helpful in diagnosing depression. (Refer to the PDQ summary on Normal Adjustment and the Adjustment Disorders ² for further information.)

Medical factors may also cause symptoms of depression in patients with cancer. Medication usually helps this type of depression more effectively than counseling, especially if the medical factors cannot be changed (for example, dosages of the medications that are causing the depression cannot be changed or stopped). Some medical causes of depression in patients with cancer include uncontrolled pain; abnormal levels of calcium, sodium, or potassium in the blood; anemia; vitamin B ₁₂ or folate deficiency; fever; and abnormal levels of thyroid hormone or steroids in the blood.

Treatment

Treatment with Drugs

Major depression may be treated with a combination of counseling and medications (drugs), such as antidepressants. A primary care doctor may prescribe medications for depression and refer the patient to a psychiatrist or psychologist for the following reasons:

• A physician or oncologist is not comfortable treating the depression (for example, the patient has suicidal thoughts).



• The symptoms of depression do not improve after 2 to 4 weeks of treatment.



• The symptoms are getting worse.



• The side effects of the medication keep the patient from taking the dosage needed to control the depression.



• The symptoms are interfering with the patient's ability to continue medical treatment.

Antidepressants are usually effective in the treatment of depression and its symptoms. Unfortunately, antidepressants are not prescribed often for patients with cancer. About 25% of all patients are depressed, but only about 16% receive medication for the depression. The choice of antidepressant depends on the patient's symptoms, potential side effects of the antidepressant, and the person's individual medical problems and previous response to antidepressant drugs.

The Food and Drug Administration (FDA) has issued a warning that patients who are taking antidepressants, such as fluoxetine (Prozac), sertraline (Zoloft), paroxetine (Paxil), fluvoxamine (Luvox), citalopram (Celexa), escitalopram (Lexapro), bupropion (Wellbutrin), venlafaxine (Effexor), nefazodone (Serzone), and mirtazapine (Remeron), should be closely monitored for signs of worsening depression and suicidal thoughts. A Patient Medication Guide (MedGuide) should also be given to patients receiving antidepressants to warn them of the risk and suggest precautions that can be taken.

The FDA has also directed manufacturers of all antidepressant drugs to change the labeling for their products to include a boxed warning and more detailed warning statements about increased risk of suicidal thinking and behavior in children and adolescents being treated with antidepressants. Some studies show that the benefits of proper antidepressant use in children and adolescents, including careful monitoring for suicidal behavior, may outweigh the risks. However, for children younger than 12 years with major depression, only fluoxetine (Prozac) showed benefit compared to a placebo.

Patients with cancer may be treated with a number of drugs throughout their care. Some drugs do not mix safely with certain other drugs, foods, herbals, and nutritional supplements. Certain combinations may reduce or change how drugs work or cause life-threatening side effects. It is important that the patient's healthcare providers be told about all the drugs, herbals, and nutritional supplements the patient is taking, including drugs taken in patches on the skin. This can help prevent unwanted reactions.

St. John's wort (Hypericum perforatum) has been used as an over-the-counter supplement for mood enhancement. In the United States, dietary supplements are regulated as foods, not as drugs. The FDA does not require that supplements be approved before being put on the market. Because there are no standards for product manufacturing consistency, dose, or purity, the safety of St. John's wort is not known. The FDA has issued a warning that a significant drug interaction occurs between St. John's wort and indinavir (a drug used to treat HIV infection). When St. John's wort and indinavir are taken together, indinavir is less effective. Patients with symptoms of depression should be evaluated by a health professional and not self-treat with St. John's wort. St. John's wort is not recommended for major depression in patients who have cancer.

Most antidepressants take 3 to 6 weeks to begin working. The side effects must be considered when deciding which antidepressant to use. For example, a medication that causes sleepiness may be helpful in an anxious patient who is having problems sleeping, since the drug is both calming and sedating. Patients who cannot swallow pills may be able to take the medication as a liquid or as an injection. If the antidepressant helps the symptoms, treatment should continue for at least 6 months. Electroconvulsive therapy (ECT) is a useful and safe therapy when other treatments have been unsuccessful in relieving major depression.

Several psychiatric therapies have been found to be helpful in the treatment of depression related to cancer. Most therapy programs for depression are given in 4 to 30 hours and are offered in both individual and group settings. They may include sessions about cancer education or relaxation skills. These therapies are often used in combination and include crisis intervention, psychotherapy, and thought/behavior techniques. Patients explore methods of lowering distress, improving coping and problem-solving skills; enlisting support; reshaping negative and self-defeating thoughts; and developing a close personal bond with an understanding health care provider. Talking with a clergy member may also be helpful for some people.

Specific goals of these therapies include the following:

• Assist people diagnosed with cancer and their families by answering questions about the illness and its treatment, explaining information, correcting misunderstandings, giving reassurance about the situation, and exploring with the patient how the diagnosis relates to previous experiences with cancer.



• Assist with problem solving, improve the patient's coping skills, and help the patient and family to develop additional coping skills. Explore other areas of stress, such as family role and lifestyle changes, and encourage family members to support and share concern with each other.



• Ensure that the patient and family understand that support will continue when the focus of treatment changes from trying to cure the cancer to relieving symptoms. The health care team will treat symptoms to help the patient control pain and remain comfortable, and will help the patient and his or her family members maintain dignity.

Cancer support groups may also be helpful in treating depression in patients with cancer, especially adolescents. Support groups have been shown to improve mood, encourage the development of coping skills, improve quality of life, and improve immune response. Support groups can be found through the wellness community, the American Cancer Society, and many community resources, including the social work departments in medical centers and hospitals.

Recent studies of psychotherapy in patients with cancer, including training in problem solving, have shown that it helps decrease feelings of depression.

Evaluation and Treatment of Suicidal Patients with Cancer

The incidence of suicide in cancer patients may be as much as 10 times higher than the rate of suicide in the general population. One study has shown that the risk of suicide in patients with cancer is highest in the first months after diagnosis, and that this risk decreases significantly over decades. Passive suicidal thoughts are fairly common in patients with cancer. The relationships between suicidal tendency and the desire for hastened death, requests for physician -assisted suicide, and/or euthanasia are complicated and poorly understood. Men with cancer are at an increased risk of suicide compared with the general population, with more than twice the risk. Overdosing with painkillers and sedatives is the most common method of suicide by patients with cancer, with most cancer suicides occurring at home. The occurrence of suicide is higher in patients with oral, pharyngeal, and lung cancers, and in HIV-positive patients with Kaposi sarcoma. The actual incidence of suicide in cancer patients is probably underestimated, since there may be reluctance to report these deaths as suicides.

General risk factors for suicide in a person with cancer include the following:

• A history of mental problems, especially those associated with impulsive behavior (such as borderline personality disorders).
• A family history of suicide.
• A history of suicide attempts.
• Depression.
• Substance abuse.
• Recent death of a friend or spouse.
• Having little social support.

Cancer-specific risk factors for suicide include the following:

• A diagnosis of oral, throat, or lung cancer (often associated with heavy alcohol and tobacco use).
• Advanced stage of disease and poor prognosis.
• Confusion /delirium.
• Poorly controlled pain.
• Physical impairments such as the following:
  • Loss of mobility.
  • Loss of bowel and bladder control.
  • Amputation.
  • Loss of eyesight or hearing.
  • Paralysis.
  • Inability to eat or swallow.
• Tiredness.
• Exhaustion.

Patients who are suicidal require careful evaluation. The risk of suicide increases if the patient reports thoughts of suicide and has a plan to carry it out. Risk continues to increase if the plan is "lethal," that is, the plan is likely to cause death. A lethal suicide plan is more likely to be carried out if the way chosen to cause death is available to the person, the attempt cannot be stopped once it is started, and help is unavailable. When a person with cancer reports thoughts of death, it is important to determine whether the underlying cause is depression or a desire to control unbearable symptoms. Prompt identification and treatment of major depression is important in decreasing the risk for suicide. Risk factors, especially hopelessness (which is a better predictor for suicide than depression) should be carefully determined. The assessment of hopelessness is not easy in the person who has advanced cancer with no hope of a cure. It is important to determine the basic reasons for hopelessness, which may be related to cancer symptoms, fears of painful death, or feelings of abandonment.

Talking about suicide will not cause the patient to attempt suicide; it actually shows that this is a concern and permits the patient to describe his or her feelings and fears, providing a sense of control. A crisis intervention -oriented treatment approach should be used which involves the patient's support system. Contributing symptoms, such as pain, should be aggressively controlled and depression, psychosis, anxiety, and underlying causes of delirium should be treated. These problems are usually treated in a medical hospital or at home. Although not usually necessary, a suicidal patient with cancer may need to be hospitalized in a psychiatric unit.

The goal of treatment of suicidal patients is to attempt to prevent suicide that is caused by desperation due to poorly controlled symptoms. Patients close to the end of life may not be able to stay awake without a great amount of emotional or physical pain. This often leads to thoughts of suicide or requests for aid in dying. Such patients may need sedation to ease their distress.

Other treatment considerations include using medications that work quickly to alleviate distress (such as antianxiety medication or stimulants) while waiting for the antidepressant medication to work; limiting the quantities of medications that are lethal in overdose; having frequent contact with a health care professional who can closely observe the patient; avoiding long periods of time when the patient is alone; making sure the patient has available support; and determining the patient's mental and emotional response at each crisis point during the cancer experience.

Pain and symptom treatment should not be sacrificed simply to avoid the possibility that a patient will attempt suicide. Patients often have a method to commit suicide available to them. Incomplete pain and symptom treatment might actually worsen a patient's suicide risk.

Frequent contact with the health professional can help limit the amount of lethal drugs available to the patient and family. Infusion devices that limit patient access to medications can also be used at home or in the hospital. These are programmable, portable pumps with coded access and a locked cartridge containing the medication. These pumps are very useful in controlling pain and other symptoms. Some pumps can give multiple drug infusions, and some can be programmed over the phone. The devices are available through home care agencies, but are very expensive. Some of the expense may be covered by insurance.

Suicide can make the loss of a loved one especially difficult for survivors. Survivors often have reactions that include feelings of abandonment, rejection, anger, relief, guilt, responsibility, denial, identification, and shame. These reactions are affected by the type and intensity of relationship; the nature of the suicide; the age and physical condition of the deceased; the survivor's support network and coping skills; and cultural and religious beliefs. Survivors should have help during this period of grieving. Mutual support groups can lessen isolation, provide opportunities to discuss feelings, and help survivors find ways to cope.

The reactions of health care providers to the suicide are similar to those seen in family members, although caregivers often do not feel they have the right to express their feelings.

Assisted Dying, Euthanasia, and Decisions Regarding End of Life

Respecting and promoting patient control has been one of the driving forces behind the hospice movement and right-to-die issues that range from honoring living wills to promoting euthanasia (mercy killing). These issues can create a conflict between a patient's desire for control and a physician's duty to promote health. These are issues of law, ethics, medicine, and philosophy. Some physicians may favor strong pain control and approve of the right of patients to refuse life support, but do not favor euthanasia or assisted suicide. Often patients who ask for physician-assisted suicide can be treated by increasing the patient's comfort and relieving symptoms, thereby reducing the patient's need for drastic measures. Patients with the desire to die should be carefully evaluated and treated for depression.

(See the PDQ summary on Last Days of Life ³ for more information.)

Considerations for Depression in Children

Most children cope with the emotions related to cancer and not only adjust well, but show positive emotional growth and development. A small number of children, however, develop psychological problems including depression, anxiety, sleeping problems, relationship problems, and are uncooperative about treatment. A mental health specialist should treat these children.

Children with severe late effects of cancer have more symptoms of depression. Anxiety usually occurs in younger patients, while depression is more common in older children. Most cancer survivors are generally able to adapt and adjust successfully to cancer and its treatment; however, a small number of cancer survivors have difficulty adjusting.

The term depression refers to a symptom or a set of symptoms or conditions that occur together and suggest the presence of depression, or an illness. A diagnosis of depression as an illness depends on how severe the symptoms are and how long they last. For example, a child may be sad in response to trauma, and the sadness usually lasts a short time. Depression, however, is marked by a response that lasts a long time, and is associated with sleeplessness, irritability, changes in eating habits, and problems at school and with friends. Depression should be considered whenever any behavior problem continues. Depression does not refer to temporary moments of sadness, but rather to a disorder that affects development and interferes with the child's progress.

Some signs of depression in the school-aged child include the following:

• Not eating.
• Inactivity.
• Looking sad.
• Aggressive behavior.
• Crying.
• Hyperactivity.
• Physical complaints.
• Fear of death.
• Frustration.
• Feelings of sadness or hopelessness.
• Self-criticism.
• Frequent daydreaming.
• Low self-esteem.
• Refusing to go to school.
• Learning problems.
• Slow movements.
• Showing anger towards parents and teachers.
• Loss of interest in activities that were previously enjoyed.

Some of these signs can occur in response to normal developmental stages; therefore, it is important to determine whether they are related to depression or a developmental stage.

Determining a diagnosis of depression includes evaluating the child's family situation, as well as his or her level of emotional maturity and ability to cope with illness and treatment; the child's age and state of development; and the child's self esteem and prior experience with illness.

A comprehensive assessment for childhood depression is necessary for effective diagnosis and treatment. Evaluation of the child and family situation focuses on the child's health history; observations of the behavior of the child by parents, teachers, or healthcare workers; interviews with the child; and use of psychological tests.

Childhood depression and adult depression are different illnesses due to the developmental issues involved in childhood. The following criteria may also be used for diagnosing depression in children:

• A sad mood (and a sad facial expression in children younger than 6) with at least 4 of the following signs or symptoms present every day for a period of at least 2 weeks:
  • Appetite changes.
  • Either not sleeping or sleeping too much.
  • Being either too active or not active enough.
  • Loss of interest or pleasure in usual activities.
  • Signs of not caring about anything (in children younger than 6).
  • Tiredness or loss of energy.
  • Feelings of worthlessness.
  • Self-criticism or inappropriate guilt.
  • Inability to think or concentrate well.
  • Constant thoughts of death or suicide.

Individual and group counseling are usually used as the first treatment for a child with depression, and are directed at helping the child to master his or her difficulties and develop in the best way possible. Play therapy may be used as a way to explore the younger child's view of him- or herself, the disease, and treatment. From the beginning of treatment, a child needs help to understand, at his or her developmental level, the diagnosis of cancer and the treatment involved. A doctor may prescribe medications, such as antidepressants, for children. Some of the same antidepressants prescribed for adults may also be prescribed for children. (Refer to the Treatment ⁴ section for information about FDA warnings on antidepressant use in children and adolescents.)

Suicide and Children

Suicide is as rare among adolescents who have no other mental disorders as it is among adults. The adolescent often believes that his or her disease is outside the realm of control, and is in the hands of God or some other force. Refusing treatment is not a way of attempting suicide, but comes from his or her belief that fate, luck, or God determines life and death.

In the general population, about 2,000 adolescents in the United States die by suicide each year. Suicide continually ranks as the second or third leading cause of death of persons between the ages of 15 and 34 years old. Children are less prone to suicide before puberty due to immature reasoning capabilities that make planning and carrying out suicide difficult. The suicide rate in young people has more than doubled during the period from 1956 to 1993. This increasing suicide rate has been blamed on the increase of adolescent alcohol abuse. Chronic and acute illnesses were not major causes of suicide in the young. The suicide rate for male adolescents is four times as high as the rate for females. The suicide rate for white adolescents is about twice as great as the rate for African-Americans and Hispanics. Little is known about the occurrence of thoughts of suicide and attempts in children with cancer.

The risk factors for the general population of children include:

• Biologic factors: Family history of mental problems such as depression, schizophrenia, alcoholism, drug dependence, and conduct disorders. Genetic predisposition to low levels of serotonin is associated with depression.



• Predisposing life events: An early family history of abuse by a parent; negative life event such as loss of a parent; childhood grief; and disturbed, hostile relationships in the family. Many other social problems and negative life events do not seem to cause suicidal behavior.



• Social factors: The very nature of adolescence itself with its desire to experiment with drugs and alcohol. Conflict or confusion about sexual orientation can be a factor in adolescent suicide. Also, characteristics such as perfectionism, impulsiveness, inhibition, and isolation all can lead to thoughts of suicide.



• Mental problems: Ninety five percent of young people who commit suicide have a mental disorder. These are usually major depression, schizophrenia, alcoholism, drug dependence, and conduct disorder. However, most children with mental problems do not commit suicide.



• Contagion: An expression that describes the phenomenon of young people identifying with others who have committed suicide. Some young people who are vulnerable may copy suicidal behavior. Friends of a patient with cancer who has committed suicide should be offered support and counseling.



• Deadly weapons available: A gun in the house can allow suicide to occur.



• Motivating events: The diagnosis of cancer can cause a person at risk to attempt suicide. Usually a mental disorder, other life stresses, an upsetting event such as a failure in school, or life-threatening disease such as cancer is already present.

Some adolescent cancer survivors may be overwhelmed by feelings of hopelessness. This may lead to thoughts of suicide. Suicide is treated by the careful evaluation of the child with cancer and his or her family. The multiple factors that can make a child's life unbearable need to be examined. Suicide prevention must include individual evaluation; referral to the correct health professionals; treatment with medications; and both individual counseling and family therapy.

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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.

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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 ¹. 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

Not normal. An abnormal lesion or growth may be cancerous, premalignant (likely to become cancer), or benign.

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

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

A quickly growing cancer.

A chemical substance found in beer, wine, and liquor. Alcohol is also found in some medicines, mouthwashes, essential oils (scented liquid taken from plants), and household products.

A disease in which a person craves alcohol, is unable to limit his or her drinking, needs to drink greater amounts to get the same effect, and has withdrawal symptoms after stopping alcohol use. Alcoholism affects physical and mental health, and causes problems with family, friends, and work. Also called alcohol dependence.

Surgery to remove part or all of a limb or appendage.

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

A drug used to treat depression.

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.

In healthcare, a process used to learn about a patient’s condition. This may include a complete medical history, medical tests, a physical exam, a test of learning skills, tests to find out if the patient is able to carry out the tasks of daily living, a mental health evaluation, and a review of social support and community resources available to the patient.

The organ that stores urine.

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 way a person thinks about his or her body and how it looks to others.

The removal of a small sample of bone marrow (usually from the hip) through a needle for examination under a microscope.

A serious mental illness marked by unstable moods and impulsive behavior. People with BPD have problems with relationships, family and work life, long-term planning, and self-identity. Symptoms include intense bouts of anger, depression, and anxiety that may lead to self-injury or suicide, drug or alcohol abuse, excessive spending, binge eating, or risky sex. A person with BPD who is diagnosed with cancer may be at an increased risk of suicide. Also called BPD.

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.

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 substance that is used to treat depression, and to help people quit smoking. It belongs to the family of drugs called antidepressants.

A mineral found in teeth, bones, and other body tissues.

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.

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

A drug used to treat depression. It belongs to the families of drugs called antidepressant agents and selective serotonin reuptake inhibitors (SSRIs). Also called Celexa.

Ordained individuals who perform spiritual and/or religious functions.

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.

A mental state in which one is not thinking clearly.

To adjust to new situations and overcome problems.

The methods a person uses to deal with stressful situations. These may help a person face a situation, take action, and be flexible and persistent in solving problems.

The process by which a professional counselor helps a person cope with mental or emotional distress, and understand and solve personal problems.

Immediate, short-term counseling (talking with a professional counselor) to stop a critical emotional incident (e.g., attempted suicide or drug overdose) from getting worse. Crisis intervention is not meant to solve the problem that led up to the crisis.

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

Dead.

In medicine, a shortage of a substance (such as a vitamin or mineral) needed by the body.

A mental state in which a person is confused, disoriented, and not able to think or remember clearly. The person may also be agitated and have hallucinations, and extreme excitement.

In psychiatry, a state in which a person is unable or unwilling to see the truth or reality about an issue or situation.

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 physical, mental, and emotional stages a child goes through as he or she grows and matures.

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

A product that is added to the diet. A dietary supplement is taken by mouth, and usually contains one or more dietary ingredient (such as vitamin, mineral, herb, amino acid, and enzyme). Also called nutritional supplement.

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.

The use of illegal drugs or the use of prescription or over-the-counter drugs for purposes other than those for which they are meant to be used, or in large amounts. Drug abuse may lead to social, physical, emotional, and job-related problems.

A change in the way a drug acts in the body when taken with certain other drugs, herbals, or foods, or when taken with certain medical conditions. Drug interactions may cause the drug to be more or less effective, or cause effects on the body that are not expected.

A treatment for severe depression and certain mental disorders. A brief seizure is induced by giving electrical stimulation to the brain through electrodes placed on the scalp. Also called ECT and electroshock therapy.

A drug used to treat depression and certain anxiety disorders. It belongs to the family of drugs called selective serotonin reuptake inhibitors (SSRIs). Also called Lexapro.

An easy or painless death, or the intentional ending of the life of a person suffering from an incurable or painful disease at his or her request. Also called mercy killing.

A record of a person's current and past illnesses, and those of his or her parents, brothers, sisters, children, and other family members. A family history shows the pattern of certain diseases in a family, and helps to determine risk factors for those and other diseases.

A type of therapy in which the whole family talks with a professional counselor to solve family problems.

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

An agency in the U.S. federal government whose mission is to protect public health by making sure that food, cosmetics, and nutritional supplements are safe to use and truthfully labeled. The FDA also makes sure that drugs, medical devices, and equipment are safe and effective, and that blood for transfusions and transplant tissue are safe. Also called Food and Drug Administration.

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

A drug used to treat depression. It is a type of antidepressant.

A drug used to treat obsessive-compulsive disorder. It is a type of antidepressant agent and selective serotonin reuptake inhibitor (SSRI). Also called Luvox.

A nutrient in the vitamin B complex that the body needs in small amounts to function and stay healthy. Folate helps to make red blood cells. It is found in whole-grain breads and cereals, liver, green vegetables, orange juice, lentils, beans, and yeast. Folate is water-soluble (can dissolve in water) and must be taken in every day. Not enough folate can cause anemia (a condition in which the number of red blood cells is below normal), diseases of the heart and blood vessels, and defects in the brain and spinal cord in a fetus. Folate is being studied with vitamin B12 in the prevention and treatment of cancer. Also called folic acid.

An agency in the U.S. federal government whose mission is to protect public health by making sure that food, cosmetics, and nutritional supplements are safe to use and truthfully labeled. The Food and Drug Administration also makes sure that drugs, medical devices, and equipment are safe and effective, and that blood for transfusions and transplant tissue are safe. Also called FDA.

Inherited; having to do with information that is passed from parents to offspring through genes in sperm and egg cells.

The normal response to a major loss, such as the death of a loved one. Grief may also be felt by a person with a serious, long-term illness or with a terminal illness. It may include feelings of great sadness, anger, guilt, and despair. Physical problems, such as not being able to sleep and changes in appetite, may also be part of grief.

Cancer that arises in the head or neck region (in the nasal cavity, sinuses, lips, mouth, salivary glands, throat, or larynx [voice box]).

Having to do with plants.

The cause of acquired immunodeficiency syndrome (AIDS). Also called human immunodeficiency virus.

Infected with the human immunodeficiency virus (HIV), the cause of acquired immunodeficiency syndrome (AIDS).

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.

A higher than normal level of activity. Hyperactivity can be used to describe the increased action of a body function, such as hormone production, or behavior. A person who is hyperactive may seem to be always moving or fidgeting, impulsive, unable to concentrate, and talking too much.

The activity of the immune system against foreign substances (antigens).

A loss of part or all of a physical or mental ability, such as the ability to see, walk, or learn.

The number of new cases of a disease diagnosed each year.

A drug that interferes with the ability of a virus to make copies of itself.

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.

A method of putting fluids, including drugs, into the bloodstream. Also called intravenous infusion.

Use of a syringe and needle to push fluids or drugs into the body; often called a "shot."

State of being separated from others. Isolation is sometimes used to prevent disease from spreading.

A type of cancer characterized by the abnormal growth of blood vessels that develop into skin lesions or occur internally.

Side effects of cancer treatment that appear months or years after treatment has ended. Late effects include physical and mental problems and second cancers.

A type of legal advance directive in which a person describes specific treatment guidelines that are to be followed by health care providers if he or she becomes terminally ill and cannot communicate. A living will usually has instructions about whether to use aggressive medical treatment to keep a person alive (such as CPR, artificial nutrition, use of a respirator).

Cancer that forms in tissues of the lung, usually in the cells lining air passages. The two main types are small cell lung cancer and non-small cell lung cancer. These types are diagnosed based on how the cells look under a microscope.

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

Refers to the practices and procedures used for the prevention, treatment, or relief of symptoms of a diseases or abnormal conditions. This term may also refer to a legal drug used for the same purpose.

A specialist who can talk with patients and their families about emotional and personal matters, and can help them make decisions.

A drug used to treat depression. It belongs to the family of drugs called antidepressant agents. Also called Remeron.

In medicine, to regularly watch and check a person or condition to see if there is any change. Also refers to a device that records and/or displays patient data, such as for an electrocardiogram (EKG).

A drug used to treat depression. It belongs to the family of drugs called antidepressant agents. Also called Serzone.

A product that is added to the diet. A nutritional supplement is taken by mouth, and usually contains one or more dietary ingredient (such as vitamin, mineral, herb, amino acid, and enzyme). Also called dietary supplement.

A doctor who specializes in treating cancer. Some oncologists specialize in a particular type of cancer treatment. For example, a radiation oncologist specializes in treating cancer with radiation.

Cancer that forms in tissues of the lip or mouth. This includes the front two thirds of the tongue, the upper and lower gums, the lining inside the cheeks and lips, the bottom of the mouth under the tongue, the bony top of the mouth, and the small area behind the wisdom teeth.

A medicine that can be bought without a prescription (doctor's order). Examples include analgesics (pain relievers) such as aspirin and acetaminophen. Also called nonprescription and OTC.

An amount of drug that is more than what should be taken at one time.

Care given to improve the quality of life of patients who have a serious or life-threatening disease. The goal of palliative 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, supportive care, and symptom management.

A disease in which malignant (cancer) cells are found in the tissues of the pancreas. Also called exocrine cancer.

Loss of ability to move all or part of the body.

A drug used to treat depression and anxiety disorders. It is a type of selective serotonin reuptake inhibitor (SSRI). Also called Paxil.

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.

Cancer that forms in tissues of the pharynx (the hollow tube inside the neck that starts behind the nose and ends at the top of the windpipe and esophagus). Pharyngeal cancer includes cancer of the nasopharynx (the upper part of the throat behind the nose), the oropharynx (the middle part of the pharynx), and the hypopharynx (the bottom part of the pharynx). Cancer of the larynx (voice box) may also be included as a type of pharyngeal cancer. Most pharyngeal cancers are squamous cell carcinomas (cancer that begins in thin, flat cells that look like fish scales). Also called throat cancer.

Medical doctor.

An inactive substance or treatment that looks the same as, and is given the same way as, an active drug or treatment being tested. The effects of the active drug or treatment are compared to the effects of the placebo.

A metallic element that is important in body functions such as regulation of blood pressure and of water content in cells, transmission of nerve impulses, digestion, muscle contraction, and heartbeat.

A doctor's order for medicine or another intervention.

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 doctor who manages a person's health care over time. A primary care doctor is able to give a wide range of care, including prevention and treatment, can discuss cancer treatment choices, and can refer a patient to a specialist.

The likely outcome or course of a disease; the chance of recovery or recurrence.

A medical doctor who specializes in the prevention, diagnosis, and treatment of mental, emotional, and behavioral disorders.

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

A specialist who can talk with patients and their families about emotional and personal matters, and can help them make decisions.

A severe mental disorder in which a person loses the ability to recognize reality or relate to others. The person is not able to cope with the demands of everyday life. Symptoms include being paranoid, having false ideas about what is taking place or who one is, and seeing, hearing, or feeling things that are not there.

Treatment of mental, emotional, personality, and behavioral disorders using methods such as discussion, listening, and counseling. Also called talk therapy.

The time of life when a child experiences physical and hormonal changes that mark a transition into adulthood. The child develops secondary sexual characteristics and becomes able to have children. Secondary sexual characteristics include growth of pubic, armpit, and leg hair; breast enlargement; and increased hip width in girls. In boys, they include growth of pubic, face, chest and armpit hair; voice changes; penis and testicle growth, and increased shoulder width.

A device that is used to give a controlled amount of a liquid at a specific rate. For example, pumps are used to give drugs (such as chemotherapy or pain medicine) or nutrients.

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.

A method used to reduce tension and anxiety, and control pain.

In medicine, an improvement related to treatment.

Something that may increase the chance of developing a disease. Some examples of risk factors for cancer include age, a family history of certain cancers, use of tobacco products, certain eating habits, obesity, lack of exercise, exposure to radiation or other cancer-causing agents, and certain genetic changes.

A group of severe mental disorders in which a person has trouble telling the difference between real and unreal experiences, thinking logically, having normal emotional responses to others, and behaving normally in social situations. Symptoms include seeing, hearing, feeling things that are not there, having false ideas about what is taking place or who one is, nonsense speech, unusual behavior, lack of emotion, and social withdrawal.

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.

A feeling of self-worth, self-confidence, and self-respect.

A hormone found in the brain, platelets, digestive tract, and pineal gland. It acts both as a neurotransmitter (a substance that nerves use to send messages to one another) and a vasoconstrictor (a substance that causes blood vessels to narrow). A lack of serotonin in the brain is thought to be a cause of depression. Also called 5-hydroxytryptamine.

A drug used to treat depression. It is a type of selective serotonin reuptake inhibitor (SSRI). Also called Zoloft.

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.

In statistics, describes a mathematical measure of difference between groups. The difference is said to be significant if it is greater than what might be expected to happen by chance alone. Also called statistically significant.

A bandage-like patch that releases medicine into the body through the skin. The medicine enters the blood slowly and steadily.

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

A professional trained to talk with people and their families about emotional or physical needs, and to find them support services.

A mineral needed by the body to keep body fluids in balance. Sodium is found in table salt and in many processed foods. Too much sodium can cause the body to retain water.

An herbal product sold as an over-the-counter treatment for depression. It is being studied for its ability to lessen certain side effects of cancer treatment. Also called Hypericum perforatum.

The extent of a cancer in the body. Staging is usually based on the size of the tumor, whether lymph nodes contain cancer, and whether the cancer has spread from the original site to other parts of the body.

A type of drug used to relieve swelling and inflammation. Some steroid drugs may also have antitumor effects.

In medicine, a family of drugs used to treat depression, attention-deficit disorder (a common disorder in which children are inattentive, impulsive, and/or over-active), and narcolepsy (a sleep disorder that causes uncontrollable sleepiness). Stimulants increase brain activity, alertness, attention, and energy. They also raise blood pressure and increase heart rate and breathing rate.

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.

In medicine, a loss of blood flow to part of the brain, which damages brain tissue. Strokes are caused by blood clots and broken blood vessels in the brain. Symptoms include dizziness, numbness, weakness on one side of the body, and problems with talking, writing, or understanding language. The risk of stroke is increased by high blood pressure, older age, smoking, diabetes, high cholesterol, heart disease, atherosclerosis (a build-up of fatty material and plaque inside the coronary arteries), and a family history of stroke.

The use of illegal drugs or the use of prescription or over-the-counter drugs or alcohol for purposes other than those for which they are meant to be used, or in excessive amounts. Substance abuse may lead to social, physical, emotional, and job-related problems.

The act of taking one's own life on purpose.

Adding nutrients to the diet.

A group of people with similar disease who meet to discuss how better to cope with their disease and treatment.

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.

One who remains alive and continues to function during and after overcoming a serious hardship or life-threatening disease. In cancer, a person is considered to be a survivor from the time of diagnosis until the end of life.

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

Disease that cannot be cured and will cause death.

Treatment.

The hollow tube inside the neck that starts behind the nose and ends at the top of the trachea (windpipe) and esophagus (the tube that goes to the stomach). The throat is about 5 inches long, depending on body size. Also called pharynx.

A hormone that affects heart rate, blood pressure, body temperature, and weight. Thyroid hormone is made by the thyroid gland and can also be made in the laboratory.

A plant with leaves that have high levels of the addictive chemical nicotine. The leaves may be smoked (in cigarettes, cigars, and pipes), applied to the gums (as dipping and chewing tobacco), or inhaled (as snuff). Tobacco leaves also contain many cancer-causing chemicals, and tobacco use and exposure to secondhand tobacco smoke have been linked to many types of cancer and other diseases. The scientific name is Nicotiana tabacum.

Injury to the body, or an event that causes long-lasting mental or emotional damage.

An antidepressant drug that is being evaluated for the treatment of hot flashes in women who have breast cancer.

A nutrient in the vitamin B complex that the body needs in small amounts to function and stay healthy. Vitamin B12 helps make red blood cells, DNA, RNA, energy, and tissues, and keeps nerve cells healthy. It is found in liver, meat, eggs, poultry, shellfish, milk, and milk products. Vitamin B12 is water-soluble (can dissolve in water) and must be taken in every day. Not enough vitamin B12 can cause certain types of anemia (a condition in which the number of red blood cells is below normal) and neurologic disorders. It is being studied with folate in the prevention and treatment of some types of cancer. Also called cobalamin and cyanocobalamin.