The use of energy from man-made ionizing radiation or from the radioactive decay of atomic nuclei to destroy diseased tissues, esp. cancers. Synonym: radiotherapy
The radiotherapy must be directed only at the diseased tissue. The patient's body is precisely measured and marked (“tatooed”), and cradles are designed to hold the patient in a precise position for each treatment. Systemic adverse effects of radiation therapy include weakness, fatigue, anorexia, nausea, vomiting, and anemia. These may subside with antiemetics, steroids, frequent small meals, fluid maintenance, and added rest and are seldom severe enough to require discontinuation of treatment although dosage adjustment may be required. Local adverse effects of radiation depend on the organ system affected. For example, radiation of the breast may sometimes result in esophagitis or pneumonitis; cranial radiation may cause hair loss; radiation treatment of head and neck cancers may cause dry mouth (for which good oral hygiene or artificial saliva may be helpful). Because radiation may affect bone marrow, patients require frequent measurement of complete blood counts. Radiation also requires special skin care, and the patient should use a hypoallergenic moisturizer (Biafine, Radiacare Gel, and Aquaphor are popular brands). Many nurses and patients prefer using natural aloe (from the leaf of an aloe plant, split open to apply the gel from inside) or bottled aloe. Usually the radiation therapist will recommend that the skin be free of any such preparations at treatment time.
conformal radiation therapy
Radiation therapy in which tumors are imaged in three-dimensions and then treated with small beams of radiation adjusted for their size, unique shape, and location. The objective is to deliver the radiation directly to the tumor and to make the energy conform to the unique shape of the tumor, leaving neighboring healthy tissue unaffected by the damaging effects. This therapy is used to treat tumors previously treated with external beam radiotherapy, tumors for which external beam radiation is also planned, and tumors that are difficult to reach or that have encircled healthy organs or tissues. Synonym: intensity-modulated radiation therapy
endocavitary radiation therapyIntracavitary radiation therapy.
intensity-modulated radiation therapy Abbreviation: IMRT.
Conformal radiation therapy.
intracavitary radiation therapy
Radiation therapy for treatment of a cancer found in hollow organs (such as the rectum, the sinuses, or the vagina) by placing the source of radiation inside the affected body cavity. Synonym: endocavitary radiation therapy
intraoperative radiation therapy Abbreviation: IORT
The administration of a large dose of radiation to a malignant tumor during surgery. After the tumor is debulked, the surrounding tissues are displaced, temporarily sutured, or protected by the applicator shield. The applicator then delivers a large dose of radiation directly to the affected tissues. IORT is used to manage otherwise unresectable tumors.
involved-field radiation therapy
A treatment for lymphoma in which therapeutic radiation is directed only to those areas involved by detectable tumor masses and not to other regions of the body
selective internal radiation therapy Abbreviation: SIRT
The treatment of solid internal organ tumors with radioactive microspheres injected directly into the target tissue, or bound to substrates that the target tissue preferentially takes up from the blood. Synonym: radioembolization; selective internal radiotherapy