Body GPS, Real-Time Tracking System Used for Prostate Radiotherapy

New technology has been developed to provide real-time tracking of tumors during prostate cancer radiotherapy treatments. The first such system to be installed in the United Kingdom, the real-time tracking method has been used to enhance the effectiveness of treatments for more than 20 prostate cancer patients at the clinic.

“This really is the gold standard for real-time tracking and we are finding that as patients learn about the system, an increasing number are requesting that we make use of Calypso transponders during their treatments,” said Neil Livingstone, treatment superintendent at Harley Street Clinic (London, UK). “We hope that an increase in precision may help minimize radiation to healthy tissue while giving our clinicians additional confidence to deliver higher doses.”


Clinicians at the Harley Street Clinic are using the real-time tracking capabilities of Calypso to lessen the amount of healthy tissue exposed to the treatment beam. Three Calypso transponders are inserted into the prostate, where they provide continuous real-time data. The position of the markers is monitored continuously throughout a treatment session to help keep the beam on target. If the targeted region moves outside the treatment beam, the treatment is automatically stopped.

Another benefit of the system, according to Mr. Livingstone, is that patients no longer need to be imaged on a daily basis, avoiding the need for additional X-ray exposure during conventional imaging. “We have great faith in the real-time tracking abilities of Calypso, which means we no longer need to image our patients as often as before,” he added.

Similar to a GPS tracking system in a car can identify where the car is at all times in relation to its destination, Calypso “GPS for the body” provides continuous real-time information as to the precise location of the prostate. The prostate can shift by as much as several millimeters during a radiotherapy treatment session. Varian Medical Systems’ (Palo Alto, CA, USA) Calypso technology enables clinicians to track the prostate in real time during treatment, in order to help enhance treatment precision. There are more than 100 Calypso installations globally and more than 15,000 patients worldwide have been treated using the system.

Recent findings demonstrated that the use of Calypso real-time tracking during radiotherapy treatments for prostate cancer resulted in a considerable decrease in most of the serious treatment-related side effects that were studied.

Related Links:
Harley Street Clinic
Varian Medical Systems