Radiation Therapy

Radiation Therapy or Radiation Oncology is a true-targeted therapy with treatment directed precisely at the site of the cancer. It may be used as part of a larger treatment strategy that includes a systemic therapy – either chemotherapy or hormonally-based therapy – or it may be administered alone. The science behind radiation oncology continues to make rapid advances in scope and technique, thus reducing side effects and sparing healthy tissues by targeting the disease more precisely.

• External Beam Radiation employs highly focused beams of energy that are directed at the cancer cells from outside the body. The planning and delivery of these beams are built upon a three-dimensional model of the individual patient, created from CT and MR scans of the patient. This 3-dimensional conformal planning uses these scans to show the exact location of the cancerous cells and the normal nearby organs, so that the safest delivery route can be determined.
• IMRT, or Intensity Modulated Radiation Therapy, is a particular type of 3D conformal radiation delivery that is well-suited to prostate cancer treatment. Using this sophisticated technique, each of the beams is modified to reduce the risk of injury to nearby normal rectum and bladder while delivering higher doses to the tumor itself.
• IGRT, or Image Guided Radiation Therapy, is a further improvement in IMRT that takes into account the fact the target and normal tissues may actually move during the time that treatment is being delivered. By using special imaging techniques, such as the placement of fiducial seeds in the prostate, or CT scans obtained immediately before each treatment, slight modifications in the setup can be made instantly that will improve the safety of the treatment by taking these motions into account.
• The Calypso® System helps doctors track the exact location of a prostate tumor DURING the actual radiation treatment for prostate cancer. This is important because organs, like the prostate, commonly move during radiation therapy because of normal bodily functions, such as digestion. By detecting the slightest movement, the Calypso system allows clinicians to reduce the size of the field being treated to deliver the maximum radiation dose to the prostate, while avoiding healthy tissue and organs. By only targeting the prostate, the Calypso System reduces the common side effects of radiation therapy in prostate cancer treatment.
  
• RapidArc™ Radiotherapy Technology is a new technology that allows for daily IGRT treatment of the prostate in a matter of 2-3 minutes, thereby reducing the time which motion can occur.
• TomoTherapy® is a new technology for IMRT delivery that divides a single radiation beam into many smaller, narrow “beamlets” that precisely conform to the tumors and minimize damage to surrounding healthy tissues.
• Brachytherapy is the placement of radioactive substances into direct contact with the target organ (prostate), thereby reducing the dose of radiation to nearby structures. These techniques require some surgical techniques. High Dose Rate (HDR) Brachytherapy uses temporary implants which are placed in a number of hollow tubes through the skin into the prostate. A single radioactive seed is then temporarily routed through these tubes on multiple occasions to deliver the radiation dose before removing the tubes. Permanent seed implantation is done under anesthesia, and a large number of radioactive seeds (tiny titanium capsules with radioactive elements such as iodine-125 or palladum-103, linked in absorbable suture material to minimize risk of migration) are inserted throughout the prostate gland and left in permanently.

VIDEO: Radiation Therapy Treatment Options for Prostate Cancer

To select a radiation oncologist who treats prostate cancer, visit our Prostate Cancer Specialists web page.

Reviewed 02/2010