Technology: Treatment Planning and Delivery: RapidArc

RapidArc is a radiation treatment therapy and a new form of Image-Guided Radiotherapy (IGRT) technology, developed by Varian Medical Systems, that allows for substantially shorter treatment times than other methods of External Beam Radiation Therapy (EBRT). In some instances, the total treatment time may be only 1/8 the time as with other approaches. It is conceivable that the accuracy of the delivery is improved over other treatment methods as moving targets, such as the prostate, have less time to move during a treatment of a shorter duration. Further, it delivers its entire volume of radiation at once, as opposed to most other techniques, which may also yield improved accuracy. Ongoing research will provide more definitive answers in the near future. UAB was the first site in the United States to treat with RapidArc, as detailed in these press releases:

More detailed information about RapidArc is available on the Varian Medical Systems website at

For more information, please view the following websites:


  • Radioisotope Therapy (RIT)
    Radiation treatment therapies that utilize radioactive sources are called radiotherapies, or radiation therapy. These sources use high-energy radiation from x-rays, gamma rays, neutrons, protons, and other sources, to kill cancer cells and shrink tumors. Radiation damages both cancer cells and normal cells by damaging their genetic material, but normal cells are able to repair themselves and resume proper function. Because of the powerful properties of radiation, proper targeting of cancer cells is essential. Treatment therapies offered at UAB can be administered either externally or internally. External radiotherapies emit radiation from a source outside the body via a machine and include “External Beam Radiation Therapy (EBRT)” and “stereotactic radiosurgery” procedures. Internal radiotherapies place radioactive materials inside the body. They may be placed in the body near cancer cells, using “brachytherapy”, or they inject or infuse a radiolabeled substance into the body via “Radioisotope Therapy (RIT)”. Radiation therapy may be used alone or in combination with chemotherapy or surgery.
  • IGRT
    IGRT is an acronym for Image Guided Radiotherapy. A cutting-edge technique, IGRT is a form of CT-Guided IMRT that continually takes multi-dimensional images during the course of treatment and based upon the images taken, adjusts the shape of the radiation beam to the shape of the tumor. The goal, of course, is to improve the accuracy with which the prescribed dose is administered to the target area, sparing healthy tissues that surround the tumor.
  • EBRT
    EBRT is an acronym for External Beam Radiation Therapy. It is a group of externally-administered radiation therapy treatments that deliver radiation to the patient via a linear accelerator. Radiation treatment therapies in the EBRT group include IGRT (Rapid Arc, Tomotherapy), IMRT, 3D Conformal Radiation Thearapy (3D CRT), Superficial, Total Skin Irradiation (TSI), and Total Body Irradiation (TBI).

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