by
Gus Iversen, Editor in Chief | February 24, 2015
From the January/February 2015 issue of HealthCare Business News magazine
Cindy Winker, senior vice-president of operations at Alliance Oncology, says that a patient’s individual needs dictate the choice in both the technology and method of radiation. “As more long-term data accrues for SRS treatment delivered with different devices, physicians are able to select the platform and proper type of radiation based on factors such as type of lesion, size and proximity to critical anatomy,” she says.
Dr. Salim Siddiqui, a radiation oncologist at Henry Ford Hospital, uses Varian linear accelerators for intracranial treatments. His hospital has performed more than 4,000 stereotactic procedures throughout the body, and their brain treatments are typically performed in a single fraction, despite the option of multi-fraction.
In March of this year, Henry Ford Hospital installed a Varian Edge linear accelerator. Siddiqui says they chose the Edge because it is more efficient and offers the same accuracy as other platforms while having the versatility to treat the entire body. Other key benefits include the 2.5mm multi-leaf collimator and a robotic couch that assists in properly positioning the patient. Those features allow for better dosimetry (dose accuracy to the tumor) and faster delivery.
With the Edge, there is also the option to extend into additional fractions when necessary. “You balance treating the target against the organ at risk,” says Siddiqui, “If you’re going to or above the tolerance of that organ then you move to three fractions. If you still can’t do it then you move to five.” With the Edge, he says they only reach three fractions in less than 10 percent of their treatments.
“When you compare Gamma Knife to linac, it was not robust enough for our stereotactic needs,” says Siddiqui, whose hospital has treated over 1,000 spine cases radiosurgically. Varian’s RapidArc (volumetric modulated arc therapy), and cone beam CT imaging capabilities make it a state of the art option for treating extracranial lesions as well as those in the brain.
“With the Edge, some spine treatments using Varian’s RapidArc planning and the higher dose rates have beam-on times of approximately 3 minutes — that makes a big difference for the spine patients suffering a great deal of pain,” says Siddiqui.
Raymond Schulz, radiosurgery manager at Varian Medical Systems, points to the efficiency of Varian’s latest linacs, (Edge and TrueBeam) as the primary feature that distinguishes them from comparable platforms. “Recent studies have shown that we are as precise, or more precise, and dosimetrically equivalent to other platforms,” says Schulz, “But we have substantial efficiency benefits.”
