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General Public -- FAQs

Q. What are cancer clinical trials? Why are they important?

A. Cancer clinical trials are conducted in hopes of finding better ways to prevent and treat cancer. Clinical trials answer important scientific questions, which can lead to future advances in care. Most of today's standard treatments are based on previous clinical trial results. Because of the progress made in clinical trials, many people with cancer are living longer. In addition to improved survival rates, clinical trials have contributed to:

  • Lower recurrence rates for many cancers
  • New treatment approaches for cancers that had no effective therapy
  • Fewer side effects from treatment
  • Better quality of life for people with cancer

Q. What are some possible benefits of clinical trial participation?

A. Possible benefits:

  • Treatment trials offer the most advanced innovations and scientific thinking in cancer care
  • If a new treatment or prevention drug or regimen is successful, trial participants may be the first to benefit from it
  • Many people derive an emotional benefit from taking part in a trial that may help others who have cancer

Q. What are some possible risks of clinical trial participation?

A. Possible risks:

  • New treatments being studied are not always more effective than standard care. They may have similar or less effective results
  • Even when a new treatment or prevention approach has benefits, not every patient who receives the treatment will experience them
  • New treatments or prevention approaches may have unexpected side effects or risks
  • The trial may impose difficulties on lifestyle, such as getting transportation to the trial site, time off from work, and child care

Q. What kinds of treatment can I expect to receive in a clinical trial?

A. The National Cancer Institute (NCI) trials use several types of treatment and prevention methods:

  • Antiangiogenesis: therapy that uses drugs to block the growth of new blood vessels to a tumor, cutting off the tumor's supply of oxygen and nutrients
  • Bone marrow transplantation: procedure that replaces bone marrow destroyed by high doses of anticancer drugs or radiation treatments
  • Chemotherapy: treatment with anticancer drugs
  • Hormone therapy: treatment that adds, blocks, or removes hormones to halt or limit cancer cell growth
  • Immunotherapy: treatment to stimulate or restore the ability of the immune system to fight infection and diseases, also called biological therapy, biotherapy, or biological response modifier therapy
  • Monoclonal antibodies: laboratory-produced substances that can locate and bind to cancer cells wherever they are in the body; each of the many monoclonal antibodies recognizes a different protein on certain cancer cells; monoclonal antibodies can be used alone, or they can be used to deliver drugs, toxins, or radioactive material directly to a tumor
  • Radiation therapy: use of X-rays, neutrons, and other sources of high-energy radiation to kill cancer cells and shrink tumors
  • Surgery: removal of a cancerous growth through an operation
  • Vaccine: a substance or group of substances meant to cause the immune system to respond to a tumor or disease; a vaccine can help the body recognize and destroy cancer cells

Q. Is there a chance I might receive a placebo or sugar pill?

A. Placebos (i.e., sugar pills) are rarely used in cancer treatment trials. No one is ever given a placebo when an effective treatment is available to treat his or her cancer. In very rare cases, a placebo may be used when testing a new drug if there is no known effective treatment for the specific cancer type or stage. If a trial does use a placebo, patients are always informed before taking part in the trial.

Q. Who can participate in cancer clinical trials?

A. Anyone who meets the medical eligibility requirements can participate. U.S. citizens and permanent residents are given first priority.

Because patient safety is of the highest concern, the NCI principal investigator and the research team make the final decision about enrolling a patient during the screening visit.

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