New Technology Reduces Time for Radiation Treatment

A next generation radiotherapy system that can significantly reduce treatment times, while also increasing the accuracy of the treatment, has been installed in the US.

The system allows for a shorter radiotherapy treatment time, resulting in less danger of tumor drift, and a reduced chance that the patient will move during irradiation.


The Halcyon radiotherapy system is manufactured by Varian Medical Systems (Palo Alto, CA, USA), and was installed at the UC San Diego Health Moores Cancer Center (UCSD; San Diego, CA, USA). This is one of only two centers in the world that treat patients using the new technology.

Using the Halcyon system oncologists can select either Intensity-Modulated Radiation Therapy (IMRT), or Volumetric modulated Arc Therapy (VMAT) to treat a patient, depending on which delivers the best outcome. The Halcyon system uses a multi-leaf collimator that shapes the radiation beam to fit the exact shape, size, and position of a tumor, and reduces the possibility that stray radiation reaches healthy tissues that surround the tumor. The system has a circular bore that is larger than standard Computed Tomography (CT) machine bores, allowing for more patient comfort, as well as a soft ambient lighting designed. According to a clinician at USCD, the new technology has a high level of automation, and results in 20% faster patient treatment times.

Professor at UC San Diego School of Medicine, Todd Pawlicki, PhD, said, "Compared to conventional radiation treatment devices, this linear accelerator is a significant technologic step forward that simplifies operation and streamlines workflow. The goal is improved patient care and a more comfortable treatment experience."