Cancer Center Launches Trilogy System for Image-Guided Radiosurgery

June 20, 2006

Norris Cotton Cancer Center at Dartmouth-Hitchcock Medical Center (DHMC) announced today that it has begun treating patients with cancer with the Trilogy System from Varian Medical Systems. Trilogy combines specialized medical imaging with precise and powerful radiation delivery, to enable advanced new therapies that shorten treatment times, reduce side effects, and offer new hope for patients previously considered to be untreatable.

Patient using Trilogy The addition of Trilogy places DHMC's Section of Radiation Oncology among the top high-technology programs in the country, and makes it the only center in Northern New England offering the newest advances in stereotactic (three-dimensional) image-guided radiotherapy and radiosurgery. "With Trilogy, we can provide the very latest in high dose, precision radiation therapy," said Alan Hartford, MD, PhD, Acting Chief of Radiation Oncology. "We can pulse radiation to tumors that move during treatment-in the lung, for example-and precisely target cancers previously considered too risky because of their location in the body or in relation to healthy organs and tissues."

Today's cutting edge radiation therapy, called radiosurgery, uses very high doses of radiation to completely eradicate a tumor in just one, or a few, treatments. High dose radiation kills cancer more effectively, but it also must be targeted more exactly, in order to leave surrounding healthy tissue unharmed. Until recently, radiosurgery had been used only in the brain, because the patient's head and tumor could be completely immobilized during treatment. Tumor size, location and movement in other parts of the body have precluded the use of high dose radiotherapy outside of the brain, called "extracranial radiosurgery."

The Trilogy System can be fine-tuned to a focal point of a one-millimeter diameter sphere, and includes high definition X-ray and CT (computed tomography) imaging, and automated patient positioning. Together, these features enable precise tracking of a tumor to ensure that each high-powered beam is delivered to the right point, at the right time. As a result, Trilogy makes stereotactic radiosurgery possible in other parts of the body, and provides important new treatment options for patients with head and neck, pancreas, lung, and metastatic cancers. Because it is less invasive and enables treatment of smaller tumors at earlier stages, Trilogy also offers an attractive alternative to traditional surgery, particularly for patients in poor health or with complicating conditions.


Norris Cotton Cancer Center combines advanced cancer research at Dartmouth Medical School with patient-centered cancer care at Dartmouth-Hitchcock Medical Center in Lebanon, NH and regional locations in St. Johnsbury, VT and Manchester and Nashua, NH. It is one of 39 centers nationwide that has achieved the depth and breadth of expertise required to earn the National Cancer Institute's "Comprehensive Cancer Center" designation. Learn more about Norris Cotton Cancer Center research, programs, and clinical trials online at

For more information, contact Mary Hawkins at (603) 653-3615