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Clinical Trial

Annual Report - 1996-1997

Clinical trial: A systematic study to evaluate a new treatment or method of administering an existing one.

Most progress in cancer therapy has been made through clinical trials, which strive to answer specific questions about new or different ways of using current treatments.

The majority of clinical trials for cancer patients analyze the effects of chemotherapeutic agents, often one compound but sometimes two or more drugs administered differently. Other studies test innovative surgical procedures to remove tumors, radiatio n therapy techniques to destroy cancer cells and biological substances that boost the body's immune system to fight cancer.

The basic goal of each clinical trial is to increase medical knowledge about a single cancer therapy or a combination of treatments and to show cancer specialists how to give a new treatment safely and effectively. In many instances, clinical trials com pare the best-known standard therapy with a newer treatment to determine if one approach increases long-term survival and/or produces fewer side effects than the other.

While most clinical trials examine methods to prevent, detect, diagnose, control and treat cancer, an increasing number of studies assess the psychological impact of the disease and ways to improve patients' comfort and quality of life.

Safety risks evaluated

All proposed new treatments go through careful laboratory and animal testing prior to being administered to cancer patients. But no matter how rigorously conducted, this early research cannot predict exactly how a new drug or other treatment will work i n humans or define all of the side effects. Thus, each patient who participates in a clinical trial provides vital information on both the efficacy and risks of a new treatment.

Anyone diagnosed with one of the more than 100 types of cancer usually is faced with several treatment decisions, including whether to have standard therapy that may be widely available and/or to take part in a clinical trial that may be conducted at onl y a few centers.

Patients who take part in clinical trials are the first to receive new research-based treatment materials or methods, which eventually may prove better than existing treatments and be added to the growing list of standard therapies. Many cancer patients have standard treatments prior to participating in clinical trials.

Depending on the type and severity of the cancer, a patient's best-and sometimes only-option may be a clinical trial. Ideally, patients and their supporting family members should discuss all treatment options with the patients' physicians.

Where to get information

The National Cancer Institute (NCI) has established a computer database about cancer and clinical trials called the Physicians Data Query (PDQ). The PDQ is updated monthly to provide patients and their doctors with the latest information on clinical tri als.

The PDQ has names of clinical researchers and hospitals where studies are in progress as well as details about clinical trials according to types of cancer. It contains summaries of more than 1,500 clinical trials open to cancer patients, including almo st 500 clinical trials available at M. D. Anderson Cancer Center.

Patients and family members can obtain PDQ information from physicians, by calling the NCI's Cancer Information Service (CIS) at 1-800-4-CANCER or on the World Wide Web (

Printed materials describing clinical trials, as well as all aspects of cancer diagnosis, treatment and rehabilitation, plus information about reducing individual risks for cancer can be requested by dialing the CIS' toll-free number.

Studies conducted in phases

Most clinical trials are carried out in phases, with each phase designed to learn specific information. Patients may be eligible for studies in various phases, depending on their general condition, the type and stage of their malignancy and what treatm ents, if any, they already have had.

Anyone entering a federally funded or regulated clinical trial in the United States is required to sign a consent form indicating an understanding of the study, including possible risks as well as benefits. If the patient is a child, a parent or guardia n must sign. Informed consent forms include names and telephone numbers for patients or family members to call with questions. The forms also tell patients they may withdraw from studies at any time.

Patients considering clinical trials should ask questions about the purpose, specific treatments and/or tests involved, monitoring procedures, possible side effects, costs, length and plans for follow-up evaluation for the studies.

Not all patients will be candidates for clinical trials nor will all who are eligible want to participate. But for those who do choose to take part, clinical trials continue to be a vital link between major scientific discoveries in the laboratory and i mproving cancer therapies. Clinical trials are the heart of translational research that seeks to extend survival and lead to higher cure rates for all cancer patients.

© 2015 The University of Texas MD Anderson Cancer Center