"Clinical trials are the cornerstone in the war on cancer. These trials answer important questions that are answered objectively, allowing physicians and patients to make educated decisions regarding optimum care."--Daniel C. Scullin, Jr, MD (2009)

Clinical trials are research studies that involve people. They are the final step in a long process that begins with research in a lab and animal testing. Many treatments used today are the results of past clinical trials.

In cancer research, clinical trials are designed to answer questions about new ways to:

• Treat cancer
• Find and diagnose cancer
• Prevent cancer
• Manage symptoms of cancer or its treatment

Cancer treatment studies are designed to answer questions about new treatments or new ways of using an old treatment and how well they work. Cancer treatment studies test many types of treatments such as new:

• Drugs or vaccines
• Ways to do surgery or give radiation therapy
• Combinations of treatments
• Many treatments used today are the results of past clinical trials.

(Taking Part in Cancer Treatment Research Studies, NIH Publication 07-6249, July 2007)

What are the different types of clinical trials?

• Treatment trials test new treatments (like a new cancer drug, new approaches to surgery or radiation therapy, new combinations of treatments or new methods such as gene therapy).
• Prevention trials test new approaches such as medicines, vitamins, minerals or other supplements that doctors believe may lower the risk of a certain type of cancer. These trials look for the best way to prevent cancer in people who have never had cancer or to prevent cancer from coming back or a new cancer occurring in people who already have cancer.
• Screening trials test the best ways to find cancer, especially in its early stages.
• Quality of Life trials (also called Supportive Care trials) explore ways to improve comfort and quality of life for cancer patients.

(What is a clinical trial, NCI website, posted 01/10/2000 and reviewed 04/08/2008)