What is Radiation Oncology?

Radiation oncology is the use of high-energy rays to treat cancer in a specific site. Radiation therapy may be used alone. It may also be used with surgery and/or chemotherapy.

Types of radiation oncology

  • External beam radiation is the most common type. Beams from a special X-ray machine (a linear accelerator) are aimed at the tumor or tumor bed from outside the body.
  • Intensity-modulated radiotherapy (IMRT) and fractionated stereotactic radiation (FSRT) are more advanced types that target cancer while causing less damage to normal tissues.
  • Tomotherapy is a form of IMRT that delivers radiation in a spiral pattern to treat certain cancers. It is a combined treatment machine and CT scanner. The CT confirms the precise size, shape and location of the tumor before the treatment is given.
  • Brachytherapy is a type of radiation therapy that delivers radiation internally by placing a radiation source in or near a tumor.
  • Stereotactic radiosurgery is used to treat some tumors, usually in the brain. It is a very precise form of radiation.

How does Radiation Oncology work?

Radiation kills cancer and normal cells in the area being treated by causing damage to the cells’ DNA. Treatments are planned to deliver as much radiation as possible to tumor cells while minimizing radiation to normal tissue. Normal cells near the cancer are able to repair damage caused by radiation. After cancer cells die, the dead cells are absorbed by your body. This process may be quite slow, so there may be a delay in the shrinkage of the tumor.

Will I need these treatments?

Your doctors will talk with you about your treatment options. If radiation therapy is needed, they will explain the type of treatment that is best for you and discuss any side effects.