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Sharp Health News

Attacking cancerous tumors, precisely

Jan. 21, 2016

Respiratory gating

Marvin Alexander, pictured with Dr. Phillip Zentner, was the first patient to undergo respiratory gating at Sharp Chula Vista Medical Center's Barnhart Cancer Center.

“It’s like a new day.”

It certainly felt that way to Marvin Alexander as he held back tears and rang the graduation bell after his final treatment for kidney cancer at Sharp Chula Vista’s Barnhart Cancer Center with his family and caregivers surrounding him.

A Navy veteran, South Bay native, husband to his wife of 20 years, and father to a teenage daughter, Marvin is also the first patient to undergo respiratory gating at Sharp Chula Vista, a technique that prevents radiation being delivered to cancerous tumors from reaching other healthy organs.

Respiratory gating is similar to deep inspiration breath hold, a technique during which a patient with left breast cancer takes and holds a deep breath, naturally creating a separation between the left breast being targeted with radiation and nearby healthy organs like the heart.

With respiratory gating, a patient’s breath is carefully tracked using an infrared camera. This tracking is important for tumors that are located near certain areas of the body, such as the diaphragm or lungs, which move as a person breathes. With this camera, radiation can be monitored with incredible precision to ensure it is only treating the cancerous tumor and not healthy tissue nearby. Should healthy tissue ever move into the area being targeted with radiation, the radiation automatically shuts off.

“Being able to track the radiation beam gives us the opportunity to turn it on or off in relation to the breathing cycle,” says Rick Michaels, lead medical physicist at the Barnhart Cancer Center. “This allows us to zero in even more accurately on the tumor and spare nearby healthy tissue from radiation exposure, which would cause negative side effects.”

Through the integration of respiratory gating, doctors are able to deliver radiation that is more powerful and more accurate than ever before to attack tumors without risking exposure to healthy tissue, which inevitably shortens the amount of radiation treatment patients must undergo.

Marvin’s new day began when he rang the bell at the Barnhart Cancer Center after only two weeks of treatment, something that would have taken much more time if it weren’t for respiratory gating. Now, instead of focusing on radiation appointments and treatment regimens, Marvin can cheer on his daughter as she accepts her high school diploma this summer. He looks forward to seeing what the future holds for his family.

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