New Linear Accelerator at SVMC Cancer Center

April 21, 2016
Copy of linacphoto3

New Linear Accelerator at Southwestern Vermont Cancer Center to More Effectively Treat Patients

By Makayla McGeeney, Bennington Banner

 Ground breaking technology such as the Varian Linear Accelerator, or linac, is a new addition to the Southwestern Vermont Cancer Center and will be able to treat early and existing stages of cancer more efficiently as well as cut down the time of treatment.

Radiation Oncologist Matthew Vernon presented the finished product at the Manchester Community Library on Wednesday. Radiation therapists traveled to Las Vegas for training and have also been in onsite training all week. They will start seeing only a few patients on Monday.

Cancer patients who typically undergo five to seven weeks of treatment, have to go to the hospital daily, and prior to the new replacement, a session would take about 20 minutes. But now, treatments will last four to five minutes with increased technology and will prevent the patient from being discomforted for a period of time. The linac is able to reduce a patient's treatment up to a total of 10 hours.

The $4 million project took about two months to complete. It included a new machine, that cost $2.5 million and a room renovation that cost $1.5 million, Vernon stated during his presentation. Fortunately, the project came in under budget because Dartmouth-Hitchcock Medical Center in New Hampshire and Northeastern Vermont Regional Hospital in St. Johnsbury purchased the machine at the same time.

Linac delivers external beam radiation treatments to kill cancer cells in various parts of the body. It utilizes Vision RT, Cone Beam Computed Tomography (CBCT), Volumetric Modulated Arc Therapy (VMAT), and Stereotactic Body Radiation Therapy (SBRT).

Vernon said that Southwestern Vermont Medical Center (SVMC) is one of the first in the area to have the Vision RT—three cameras and laser arrays, which monitors the patient during radiation treatment. CBCT is on-board imaging capability to track the progress of photos of a tumor's internal position. This allows radiation to hit the tumor directly without affecting normal tissue, which can lead to side effects in the short and long term, according to Vernon.

The VMAT can actually shape the patient's body in real time, similar to an art stencil, and provide radiation while changing the level of output as it moves around the tumor. With the old linac, beams were shot from seven to 10 different angles, but the Varian rotates entirely around the patient on the table.

In the control room on the other side of a thick, concrete wall, radiation therapists and a dosimetrist look at about six screens displaying data while learning how to operate the linac and use new software. Chief Radiologic Therapist Erin Roy said she felt overwhelmed with the training and hadn't operated on a Varian machine since college. She also just returned from maternity leave.

"We're learning how to use the imager and other basic things like machine startup and warm-up," she said. "We need to check the output every morning. A trainer will be here next week to help us and go into depth with things."

When a patient goes into treatment, they can look up at the ceiling and see a realistic sky view with tree tops to create a more relaxing atmosphere. Vernon said with the maple leaf incorporated into the hospital's logo, they decided to continue the environmental treetop scene. The previous setup displayed a night scape scene. The renovated room includes cabinet space that line the walls, which is different from exposed equipment in the former room.

The room is also mic'd and has cameras in case of an emergency. Radiologists are always monitoring the unattended patient during treatment from the control room.

When a patient is diagnosed with cancer, they first go through a simulation and get little blue permanent dots to signal where tumors are located throughout the body. At this time Vernon maps out a scan so that radiation is correctly targeted.

"What we do on this day needs to be reproducible throughout," he said in regards to positioning and targeted locations.

Because stage one tumors are being found in lung cancer patients, Vernon said the word needs to be spread to primary care establishments that linac is a solution over surgery. He added that the hospital hopes to combat lung cancer further, but acknowledges that people aren't smoking as much as they used to and rates have already decreased.

Additionally, a nutritionist, nurse and other supportive care is getting involved to "come together as a comprehensive cancer center," Vernon said. Currently there are three radiation therapists.

"We're able to treat more patients close to home," Vernon said.

The oncologist consults with peers from surrounding institutions weekly about abnormal cancer cases and supported his efforts by saying "Cancer doesn't read a textbook."