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Find A Radiation Oncologist

Clinical Trials


Cancer specialists regularly conduct studies to test new treatments. These studies are called clinical trials. Most standard cancer treatments are based on the results of previous clinical trials. Clinical trials are available through cancer doctors everywhere — not just in major cities, university centers or in large hospitals.

Some clinical trials try to determine if a therapeutic approach is safe and potentially effective. Many large clinical trials compare the more commonly used standard treatment with a treatment that cancer experts think might be better. Patients who participate in clinical trials help doctors and future cancer patients find out whether a promising treatment is safe and effective. Clinical trials should be reviewed by an independent ethics committee that approves and monitors the research study such as an institutional review board (IRB). All patients who participate in clinical trials are carefully monitored to make sure they are getting quality care. Enrolling in clinical trials is completely voluntary. You can leave a trial at any time. Clinical trials testing new treatments are carried out in phases.

Phase I — Is the Treatment Safe?

When doctors are developing a new treatment, the first step is to determine the maximum safe dose of treatment that can be administered. This needs to be done before any determination of whether the drug is effective. Radiation phase I trials are different since radiation oncologists already know the standard doses of radiation that are effective. Phase I radiation trials may investigate combining radiation therapy with other treatments such as surgery or drugs or evaluate new techniques of delivering radiation therapy. These trials examine if the new treatment is safe and feasible.

Phase II — Does the Treatment Work?

In a phase II radiation study, radiation oncologists are trying to establish if the new treatment is effective. Researchers want to know if the new treatment shows enough promise in terms of controlling the tumor that it is worth testing against the standard therapy in a phase III trial. Side effects are closely monitored.

Phase III — Is the Treatment Better?

Phase III trials compare the new treatment against the current standard therapy and randomly assign patients into one of two groups. This is the gold standard of clinical research trials. If a new treatment is shown to be better than standard treatment in terms of cancer control and side effects in a phase III trial, experts will reconsider standard of care treatment.

Phase IV — Are There Better Ways to Use the Treatment?

In this final step, treatments are tested to make sure they are safe and work well over a long period of time. This phase most often occurs once the new treatment has been approved for standard use. Several hundred to several thousand people are enrolled in a phase IV trial.

Deciding to participate in a clinical trial is a personal decision that only the patient can make. Before enrolling, patients should learn as much as possible about cancer treatment and the clinical trials that are available. Patients should ensure that the clinical trial has been reviewed by an IRB. The radiation treatment team can answer any questions if a patient is considering a trial.

View clinical trials resources.