TYPES OF RADIATION THERAPY

Radiation therapy is essentially given in two ways: externally through a linear accelerator (external beam radiation), or internally by the implantation of radioactive sources (brachytherapy). The method your radiation oncologist chooses will depend on the type of cancer you have and the location of your tumor.

Radiation Setup
Radiation Setup

External Beam Radiation

  • Intensity-modulated radiation therapy (IMRT)
  • Aperture-modulated radiation therapy such as conformal arc or the RapidArc®
  • 3-D conformal radiation therapy
  • Stereotactic radiosurgery (SRS) with Gamma-knife, Cyberknife
  • Stereotactic body radiotherapy (SBRT) with Cyberknife or Trilogy-Linac
  • Total body irradiation (for bone marrow transplant patients)
  • Total skin irradiation
  • 3-D virtual simulation with multi-modality image registration including 4D CT, PET, MRI (dynamic contrast enhancement is routinely used for prostate patients)
  • Image-guided target localization including Ultrasound-based, kV X-rays-based, CBCT-based and non-ionizing electromagnetic-based (Calypso® 4D) systems
  • Respiratory gated radiation therapy

External therapy treatments for cancer are usually done five days a week for six to seven weeks or more. Palliative pain-reducing treatments take less time. A care plan is designed specifically for each patient and takes into consideration the radiation dose; the size, location and type of cancer; and the patient’s overall heath. Spreading the treatments over several weeks is also advantageous over having a fewer number of larger doses, because it helps protect normal body tissues. Weekend rests give normal cells a chance to recover.

HDR Brachytherapy
HDR Brachytherapy

Brachytherapy

Our brachytherapy program covers:

  • Low-dose-rate gynecologic brachytherapy using Cs-137 radioactive tubes
  • Interstitial implants using Ir-192 radioactive seeds
  • Prostate permanent seed implantation using I-125 or Pd-103 radioactive seeds
  • Prostate temporary high-dose-rate implant using Ir-192 high dose radiation remote afterloader
  • I-125 eye plaque implant for ocular melanoma
  • MammoSite high dose radiation program for early stage breast cancer
  • Radioembolization with yttrium-90 microspheres: a state-of-the-art brachytherapy treatment for primary and secondary liver malignancies

When the cancer is best treated with a high dose of radiation delivered internally to a very small area, brachytherapy is given. For these patients, radioactive material is delivered directly into the cancerous tissue in the form of seeds or capsules implanted by catheters under mild anesthesia. How long the implant stays in the body depends on the type of cancer, dose of radiation, overall health and other treatments the patient may have had. Low-dose radiation implants may be removed after a few days. High-dose implants may only need to stay in place for a few minutes. Permanent implants use short-lived radioisotopes which give out radiation in a short period of time and decay to non-detectable levels.