New Cancer Treatment Technology

linacdoneDelivering the highest level of care requires investments in the latest technology. Through its partnership with Dartmouth-Hitchcock, the Cancer Center at Southwestern Vermont Medical Center has purchased a new linear accelerator, known as a linac, for improved cancer care.

The device—which delivers external beam radiation treatments for patients with cancer—is used to treat cancer cells in all parts and organs of the body. The replacement of the current linac with this state-of-the-art unit allows SVMC to treat a broader range of cancers more comfortably.

“Radiation patients typically undergo 5 – 7 weeks of daily treatments. This technology allows us to improve every aspect of that challenging time; treatments will be faster and more targeted,” said Matthew Vernon, MD, radiation oncologist. “The benefit to local patients will be tremendous.”

Each of technologies available on the new linac relates directly to a benefit to patients:

• Two of the technologies—VisionRT, which consists of a system of laser and camera arrays, and Cone Beam Computed Tomography (CBCT), an on-board imaging capability—improve the accuracy of patient positioning and targeting of cancerous tissue. As a result, Vernon can prescribe treatment to a smaller area, which decreases radiation exposure to healthy tissue and lessens side effects.

• A special gating capability accounts for tumor motion resulting from patients’ breathing. A detector marks the patient's breathing and the beam turns off at the extremes of inhalation and exhalation. As a result, the device irradiates only when the tumor appears in the middle of a breathing cycle. The smaller target field relates to decreased exposure to normal tissue, decreased toxicity, and fewer side effects.

• As in the past, a multi-leaf collimator shapes the beam, directing the beam to the area prescribed. The new linac allows for Volumetric Modulated Arc Therapy (VMAT), which means that the machine rotates around the patient during treatment while the radiation blocking collimator mechanism adjusts to shape the beam. This allows Vernon to treat a tumor continuously from multiple angles with a beam shape programmed to match the tumor shape throughout the movement. This feature improves the patient experience by reducing the length of time patients must remain motionless in an uncomfortable position. Treatments that had lasted 20 minutes will take 4 – 5 minutes, a reduction of time of up to 75 percent.

• The addition of Stereotactic Body Radiation Therapy (SBRT) will allow the Cancer Center to treat patients with several types of cancer right here. In the past, the same patients would have been referred to centers further from home. In addition, the technology is used to treat early stage lung cancer, especially for patients whose lungs would not withstand aggressive surgery that is usually recommended. Cure rates are comparable in 3 – 5 treatments with mild toxicity.

• In addition, the new linac vault has been attractively redesigned with a focus on natural materials and natural light.

“This technology improves the patient experience by providing treatment more comfortably in less time and with fewer side effects,” said Vernon. “We are already providing the highest standard of care.”

The unit and the renovation necessary to install it will cost a total of more than $4 million. A significant savings resulted from SVMC’s partnership with Dartmouth-Hitchcock. The cost will be offset through philanthropic contributions, some of which have already been made to the initiative. Renovation and installation of the linac began in February, and patient treatments began earlier this month. An announcement of philanthropic partners will be released as the project nears completion.