Glossary of Medical Terms

A substance being studied in the treatment of brain tumors and some other types of cancer. It increases the amount of oxygen in tumor tissues, which may make the tumor cells easier to kill with radiation therapy. Efaproxiral is a type of radiosensitizing agent. Also called RSR13.

A drug used with other drugs to treat infection with the human immunodeficiency virus (HIV). It blocks HIV from making copies of itself. It is a type of non-nucleoside reverse transcriptase inhibitor and a type of antiviral agent. Also called Sustiva.

A cell that performs a specific function in response to a stimulus; usually used to describe cells in the immune system.

A drug used to treat depression and certain anxiety disorders. It may also be used to treat hot flashes in women who are in menopause or are being treated for breast cancer. Effexor increases the levels of the chemicals serotonin and norepinephrine in the brain, which helps improve mood. It is a type of antidepressant and a type of serotonin-norepinephrine reuptake inhibitor. Also called venlafaxine.

Effectiveness. In medicine, the ability of an intervention (for example, a drug or surgery) to produce the desired beneficial effect.

An abnormal collection of fluid in hollow spaces or between tissues of the body. For example, a pleural effusion is a collection of fluid between the two layers of membrane covering the lungs.

A substance that is being studied in the prevention of cancer. It belongs to the family of drugs called antiprotozoals.

In cancer, the length of time after primary treatment for a cancer ends that the patient remains free of certain complications or events that the treatment was intended to prevent or delay. These events may include the return of the cancer or the onset of certain symptoms, such as bone pain from cancer that has spread to the bone. In a clinical trial, measuring the EFS is one way to see how well a new treatment works. Also called event-free survival.

A group of cancers that includes Ewing tumor of bone (ETB or Ewing sarcoma of bone), extraosseous Ewing (EOE) tumors, primitive neuroectodermal tumors (PNET or peripheral neuroepithelioma), and Askin tumors (PNET of the chest wall). These tumors all come from the same type of stem cell. Also called Ewing sarcoma family of tumors.

A drug used as a cream to treat actinic keratosis (a skin condition that may become cancer). It is also used as a cream to treat basal cell skin cancer that is superficial (not invasive) and cannot be treated with other therapy. Efudex stops cells from making DNA and may kill cancer cells. It contains the active ingredient fluorouracil. Efudex is a type of antimetabolite.