Calypso: Talk to us about becoming a patient Learn more

What is Calypso?

Calypso® by Varian involves using radiofrequency transponders which are surgically placed in tumours to track and adjust radiation treatment beams due to natural movements of the body, such as breathing.

Radiation therapy for cancer treatment requires the accurate delivery of radiation to the tumour, with as little radiation as possible delivered to the surrounding healthy tissues and organs.

Even when you are lying stationary during radiation therapy, the organs in your body move slightly when you breathe in and out. The precise position of the organs in your body can also shift slightly from day to day due to natural variations in your body. For example, the precise location of a tumour of the prostate can change very slightly depending how full your bladder is or how much gas is present in the rectum.

How does Calypso work?

Your doctor will perform a small surgical procedure to implant the Calypso radiofrequency transponders inside your cancer or tumour. The transponders are small, approximately 8mm long – about the size of a grain of rice.

Once in place, the transponders will continuously transmit real-time information to the Calypso tracking system using radiofrequency waves.

This information is used to guide the delivery of your radiation therapy and allows your doctor to make any fine adjustments that may be required during treatment.

What are the benefits of Calypso?

The Calypso system gives your doctor and your treatment team information about the precise location of your tumour and information about any small movements during treatment that may be caused by the natural movements of your body.

By knowing the precise location of your tumour and tracking any movement, radiation therapy can be delivered more accurately to a smaller treatment area. This means there is less radiation delivered to the surrounding healthy tissue with less side effects.

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