Surface guided radiation therapy (SGRT)

GenesisCare has invested in technology to ensure that our patient treatment is delivered accurately, every time.

What is surface guided radiation therapy? (SGRT)

Surface Guided Radiation Therapy (SGRT) is a tattoo-free alternative for patients who require radiation therapy. The technology uses advanced 3D camera technology to track and monitor your movements during set-up and treatment.

This technique uses an infrared camera that provides the radiation therapist with thousands of reference points on your skin which allows them to precisely track any movements, in real time, to ensure the radiation is delivered to the targeted area, safely and with sub-millimetre accuracy.

Safety is further enhanced by the system’s auto-pause feature, which automatically stops treatment if you happen to move outside the targeted position.

How does SGRT work?

SGRT uses sophisticated 3D camera technology to accurately target radiation treatment.

  • Accurate positioning and motion tracking eliminate the need to have permanent tattoos made on your body.
  • During your radiation planning and treatment patterned light and imaging technology are used to detect and monitor your exact position, with sub-millimetre accuracy, to make sure the radiation is precisely targeted.
  • SGRT is often used to assist Deep Inspiration Breath Hold (DIBH) treatment for left-sided breast cancer with the benefit of minimising the radiation dose to the heart.
  • The treatment sessions are typically shorter than traditional radiation therapy sessions, due to the faster set-up, so less time is spent on the treatment table.
  • SGRT can be used for both left and right sided breast cancer.

Why SGRT for left-sided breast cancer?

When treating cancer with radiation therapy, our goal is to deliver radiation to your breast area while protecting surrounding healthy tissue from exposure and potential damage.

The proximity of the left breast to the heart leaves the heart vulnerable to radiation exposure. This has been shown to lead to serious long-term cardiac complications¹.

Deep Inspiration Breath Hold (DIBH) is a technique to move the heart away from the breast during treatment. SGRT monitors any tiny movements between your planned and actual position, in both normal breathing and when you are holding your breath. It continues to monitor you during the breath hold treatment. If you move outside the planned position, SGRT will automatically pause the treatment. Treatment will resume only when you are once again in the correct position.



What to expect

Planning and treatment with DIBH

During treatment planning, you will be asked to lie on your back for a planning CT scan to be taken of your body.

After ensuring you are comfortably positioned you will be asked to take and hold a deep breath, starting with 5-10 seconds, working up to 20-30 seconds.  You will have the opportunity to practise this breath hold with the support and guidance from your radiation therapist. This is to ensure that your heart is as far from your breast area as it can be. Once you are comfortable with the breath hold a CT scan will be performed.

For treatment you will be placed in the same position as for the CT scan. The radiation therapists will guide you through both this set up process, and your treatment. If DIBH is required, you will be instructed when to take a deep breath and when to breath out. SGRT will monitor you closely at all times.



¹ Darby et al. Risk of Ischemic Heart Disease in Women after Radiotherapy for Breast Cancer.N Engl J Med 2013; 368:987-998.

* This is a typical treatment for left breast radiation therapy, however individual circumstances may vary.

* Images and some content courtesy of VisionRT –

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