Varian Medical Systems said that a 36-year-old female lung cancer patient has become the first person in Switzerland to be treated using a highly-targeted radiotherapy technique called extra-cranial stereotactic radiotherapy. Using the company’s equipment, the team at Lindenhofspital in Bern has successfully delivered three highly-focused, radiotherapy doses aimed at destroying a small tumor on the patient's lung.
Leon Andre, MD, medical physicist at the private Lindenhofspital, said the tumor has shrunk as a result of the treatment and the patient is now recovering well. The treatment took place using a Varian Clinac 23EX linear accelerator with a 120-leaf MLC (multileaf collimator) to enable clinicians to narrow down the beam to millimeter accuracy, thereby reducing the risk of side effects.
"Surgery was not an option for this patient because her other lung had been removed a year ago," said Andre. "A new tumor appeared on her remaining lung and we decided that the best option would be to deliver three high-dose stereotactic treatments over a ten-day period. We are very pleased with the way the patient has responded to this new stereotactic treatment."
Stereotactic radiation therapy treatment is often used for cranial tumors but recent advances in real-time imaging equipment and beam-shaping devices have broadened its use to the rest of the body. Varian’s On-Board Imager is an imaging device that extends from the linear accelerator and enables highly accurate image guided radiotherapy treatments, and the 120-leaf Millennium multileaf collimator allows the beam to be shaped to extreme levels of precision, Varian said.
"The purpose of extra-cranial stereotactic radiotherapy is to increase the dose to achieve the best possible tumor control rates while minimising the risk of side effects," said Andre. "This can only be achieved by decreasing the amount of normal healthy tissue that is exposed.
"The recent availability of IGRT solutions in general and conebeam CT imaging in particular have meant a tremendous improvement in treatments," he added.