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Fact Sheet
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    Reviewed: 06/20/2005
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PDQ®: Questions and Answers

Key Points
  1. What is PDQ?
  2. PDQ is a comprehensive cancer information database that is updated regularly. PDQ contains the most current information about cancer treatment, supportive care, screening, prevention, genetics, and complementary and alternative medicine (CAM). The database also contains abstracts of clinical trial protocols (action plans for conducting clinical trials). PDQ is maintained by the National Cancer Institute (NCI) with the help of cancer experts from across the Nation.

  3. What information is included in PDQ?
  4. PDQ contains the following information:

    • Treatment Summaries for Patients and Health Professionals: peer-reviewed, detailed staging and treatment information for more than 80 different types of adult and pediatric cancer.

    • Supportive Care Summaries for Patients and Health Professionals: peer-reviewed information on the assessment and management of problems and conditions commonly associated with cancer and its treatment.

    • Screening Summaries for Patients and Health Professionals: peer-reviewed summaries of the latest information about cancer screening for major cancer sites.

    • Prevention Summaries for Patients and Health Professionals: peer-reviewed summaries of the latest information about cancer prevention for major cancer sites.

    • Genetics Summaries for Health Professionals: peer-reviewed information on the genetics of selected cancers and inherited genetic factors that can influence cancer risk.

    • Complementary and Alternative Medicine Summaries for Health Professionals: peer-reviewed summaries of the latest information about the use of CAM in the treatment of cancer.

    • Clinical Trial Protocols: ongoing and closed clinical trials from around the world. Protocol abstracts are available in health professional and patient formats.

  5. What information is in the cancer information summaries?

    • Treatment Summaries: PDQ treatment summaries contain a description of prognosis (probable outcome), cellular classification (tissue type), staging (extent of disease), and treatments for all major cancers and some cancer-related conditions.
    • The treatment summaries describe therapies currently available for a specific type and stage of cancer. PDQ does not recommend one treatment over another, but lists treatment options that health care providers may consider in developing a treatment plan to meet a patient’s needs. Because advances in treatment occur frequently, PDQ summaries are reviewed regularly by PDQ Editorial Board oncology experts and are updated as needed.

    • Supportive Care Summaries: PDQ supportive care summaries contain information about health problems caused by cancer and/or its treatment. The supportive care summaries cover such subjects as nutrition, sexuality, pain, nausea, and vomiting.

    • Screening Summaries: PDQ screening summaries contain information that describes tests and procedures used to screen for certain types of cancer.

    • Prevention Summaries: PDQ prevention summaries contain information that describes risk factors and methods to increase chances of preventing particular types of cancer.

    • Genetics Summaries: PDQ genetics summaries contain information about inherited genetic factors that may affect cancer risk. These summaries also include information about the genetics of selected cancers.

    • Complementary and Alternative Medicine Summaries: PDQ CAM summaries contain information about CAM treatments. Though only available in health professional versions, the CAM summaries are written in less technical language and include definitions of medical and scientific terms.

    Most cancer information summaries are available in two versions: a technical version for health professionals and a nontechnical version for patients, their families, and the public. A growing number of the patient versions of summaries include illustrations and definitions of the medical and scientific terms used. Many summaries are also available in Spanish.

  6. What are clinical trials?
  7. Clinical trials are research studies in which human volunteers participate. There are many types of clinical trials. They include studies to evaluate methods for prevention, detection, and treatment of cancer, as well as studies designed to lessen the distress of the disease and improve comfort and quality of life. Each trial is designed to answer scientific questions. People who take part in clinical trials have the first opportunity to benefit from new research and make very important contributions to medical science.

  8. What information about clinical trials is in PDQ?
  9. PDQ provides abstracts of ongoing treatment, supportive care, diagnostic, genetics, screening, and prevention clinical trials, including all NCI-funded clinical trials and some studies conducted by independent investigators at hospitals and medical centers in the United States and other countries around the world. Most of the trials in PDQ are designed to evaluate new treatments for cancer patients. Each abstract includes information such as the trial’s purpose, the requirements for being eligible to participate, and names and phone numbers for obtaining further information.

  10. What are the ways of obtaining information from PDQ?
  11. Listed below are several ways to access information from PDQ.

    • Cancer topics section of the NCI’s Web site: The NCI’s Web site contains PDQ cancer information summaries about treatment, supportive care, screening, prevention, genetics, and CAM; PDQ clinical trials information; and other related information. The Web site also contains information from PDQ’s Cancer Genetics Services Directory, which is a directory of individuals who provide services related to cancer genetics.  The cancer information area may be accessed at on the Internet.

    • Clinical trials section of the NCI’s Web site: The clinical trials area of the NCI’s Web site is the Institute’s comprehensive clinical trials information center for patients, health professionals, and the public. It includes information on understanding trials, deciding whether to participate in trials, and finding specific trials listed in PDQ, plus research news and other resources. The clinical trials area may be accessed at on the Internet.

    • Cancer Information Service: Cancer patients, their families, health professionals, and the public can obtain PDQ information by calling the NCI’s Cancer Information Service (CIS) at 1–800–4–CANCER (1–800–422–6237). Deaf and hard of hearing callers with TTY equipment may call 1–800–332–8615. Information specialists at the CIS use PDQ cancer prevention, screening, treatment, supportive care, CAM, and genetics summaries; clinical trials information; and other NCI resources to answer callers’ questions about cancer. They can also send PDQ information and NCI materials to callers. Hours of operation for the CIS are Monday through Friday, 9:00 a.m. to 4:30 p.m. local time.
    • The CIS also provides live, online assistance through the LiveHelp link on the NCI’s Web site. Through LiveHelp, an instant messaging service, information specialists provide Internet users with help in locating PDQ summaries, searching for clinical trials, navigating the NCI’s Web site, and finding answers to questions about cancer. LiveHelp is available Monday through Friday, 9:00 a.m. to 11:00 p.m. Eastern time.

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Related Resources

Publications (available at

National Cancer Institute (NCI) Resources

Cancer Information Service (toll-free)
Telephone: 1–800–4–CANCER (1–800–422–6237)
TTY: 1–800–332–8615

NCI’s Web site:
LiveHelp, NCI’s live online assistance:

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