Radiotherapy, Radiosurgery Treatments Developed for Prostate Cancer, Lung Cancer, Schwannomas, Brain, and Spinal Metastases

A Swiss hospital has become the first medical center in the world to begin treating cancer patients with a new technology, a new platform for image-guided radiotherapy and radiosurgery that was designed to treat a moving target with extraordinary speed and precision.

The University Hospital of Zürich (Switzerland) is one of two of the world's premier cancer centers to install a TrueBeam system, developed by Varian Medical Systems, Inc. (Palo Alto, CA, USA), and began using the system clinically in March of 2010. Since then, doctors there have delivered treatments for prostate and lung cancer, as well as schwannomas (benign nerve sheath tumors), brain, and spinal metastases.

"We are finding the system technically wonderful, giving us dose distributions that are slightly superior to IMRT [intensity-modulated radiation therapy] from a conventional system, with lower doses to surrounding healthy tissues,” said Prof. Urs M. Lütolf, M.D., clinical director and chairman of the department of radiation oncology at Zürich University Hospital. "I have been astonished and excited to see the degree to which the image isocenter matches the beam isocenter, at a level of precision I have never seen before.”

Two patients with vestibular schwannomas were the first to receive RapidArc stereotactic radiosurgery treatments on the hospital's new TrueBeam system. At the highest dose delivery rate available on the system, these treatments took just over 1.6 minutes to deliver--treatments that would require 6-8 minutes at conventional dose delivery rates. "It's a quarter of the time we needed for this type of treatment before,” said Dr. Lütolf. In addition, these treatments took advantage of the system's ability to deliver RapidArc treatments from a flexible range of angles to maximize the dose to the targeted tumor and avoid important nearby critical structures.

Dr. Lütolf reported that while early TrueBeam treatments were focusing on prostate and schwannomas, there are plans to extend treatments for lung and upper gastrointestinal (GI) tract cancers such as pancreas and gall bladder, along with palliative treatments where he described the precision of the TrueBeam system as "imperative” in reducing side effects. "The experience so far is of better precision delivered in considerably less time,” he said. "It is very satisfying to monitor the treatment while it's underway, as you can see the prostate markers are not moving even a millimeter.”

"Clinical tools and processes have been reimplemented from scratch into the TrueBeam design,” observed Jan Hrbacek, scientific collaborator at Zürich University Hospital.” This strategy has simplified a wide spectrum of activities, while increasing the accuracy of performed processes and our control over them.”

Related Links:
University Hospital of Zürich
Varian Medical Systems