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What is Radiotherapy?

This information has been generously supplied by our primary sponsor, Varian Medical Systems. Varian is the world's leading manufacturer of medical devices and software for treating cancer and other medical conditions with radiotherapy, radiosurgery, proton therapy, and brachytherapy.

Benefits & Side Effects

Radiation therapy, also called radiotherapy, is the branch of medicine that deals with the treatment of cancer by delivering high-energy beams directly to a tumor, or intended target.

Radiation therapy is a common form of treatment for cancer today. According to the American Society of Radiation Oncology (ASTRO), more than 60% of cancer patients will receive radiation therapy - either alone or in combination with other treatment approaches, such as surgery and chemotherapy. Each case is unique and your physician is the best person to decide on the suitability of radiation therapy for your treatment.

Radiotherapy has two equally important goals: to control the growth of the tumor and to do so while minimising exposure to the surrounding normal, healthy tissue. Radiotherapy is broadly divided into external beam radiation therapy (EBRT), where radiation is delivered to the target from an external machine, and brachytherapy, where radiation is delivered by placing the radiation source inside the body near the intended target. Both techniques are used for treating a large variety of tumor types.

How does radiotherapy work?

Radiotherapy uses a focused beam of energy to damage cancerous cells while minimising exposure to healthy tissue. Radiation damages the DNA in cancer cells, which interrupts their ability to reproduce, causing them to die and the tumor to shrink. Normal cells can recover from radiation more easily.

Treatment is delivered to the target site with a machine called a linear accelerator or linac. The linac generates a high-energy beam, which is delivered from many different angles, to target each part of the tumor and deliver the prescribed amount of radiation. Typically, treatment is delivered over several weeks.

When designing your treatment plan, your medical team relies on one or more types of 3-D scans of your body. These can include a CT scan, an MRI, and/or a PET scan. By looking at these scans and other test results, the radiation oncologist and his or her treatment team determine which treatment technique is best suited for your particular case. Read more...

How radiotherapy is used

Radiation therapy can be used to treat many cancers, alone or in combination with other treatments. It can be used:

  • to treat a cancer and attempt to prevent a recurrence by eliminating a tumour
  • as a palliative treatment when eliminating the tumour is not possible. (Palliative radiation therapy is intended to relieve pain, pressure and other symptoms by shrinking the tumour)
  • before surgery to help shrink the tumour
  • after surgery to treat any remaining cancer cells
  • in combination with chemotherapy treatment

Benefits of radiotherapy

If radiation therapy is recommended as part of your treatment, potential benefits may include:

  • many patients find that their radiation therapy sessions have a minimal effect on their daily schedules.
  • treatment sessions are typically given on an outpatient basis, meaning no hospital stay is required.
  • sessions typically takes less than an hour, and sometimes as little as 15 minutes—from entering the waiting room to leaving the hospital or clinic. Read more...

For further information, please visit the comprehensive Radiation Therapy section on Varian's website, which includes information such as what to expect, treatment techniques, possible side effects and what to ask your doctor


"New radiotherapy machines are improving cure rates in Australia by 15%" (Source: The Australian)