A New GPS System for Battling tumors
October 25, 2016

Eliminating tumor cells through radiotherapy is like shooting down enemies in a battlefield. Both need their mission completed with minimum collateral damage. One thing infantrymen have learned over years of field operations, however, is that real targets don’t stand still waiting to be shot; they move. And so do tumor cells. Thanks to a $1.5 million grant by the Henry L. Guenther Foundation, radiation clinicians at Torrance Memorial Medical Center recently upgraded their armory with the new Varian TrueBeam® slim linear accelerator, the latest “precision-guided munition” to be used in the battle against tumor cells.

In 2013, Torrance Memorial became the first hospital in the South Bay to treat cancers with TrueBeam. The grant funds the purchase of an additional, slightly more advanced unit, which offers what can be described as a “GPS tracking system” for pinpointing tumors.

“The most important new technology we are gaining with the new TrueBeam unit is the Calypso® Extracranial Tracking System,” says Thyra Endicott, MD, a radiation oncologist at Torrance Memorial. “By implanting radiofrequency-activated markers within the target, Calypso enables us to track tumor movements in real time during the treatment delivery.”

Variable and unpredictable, tumor movements are often caused by patient movements or internal movement of the tumor within an organ, such as lung or bladder. If these movements can be tracked, the radiation beam can be made smaller to reduce the dose to adjacent normal tissue.

To minimize risk, the Calypso Tracking System monitors the whereabouts of targeted tumor cells through uninterrupted radiofrequency signals from electromagnetic transponders that are placed in the target lesion during a simple outpatient procedure. It then interprets the target’s location on lateral, longitudinal and vertical axes. With this objective information on hand, the clinician can adjust the radiation beam at any time during the procedure in accordance with the slightest change of the location of the target cell. The system also automatically stops radiotherapy if the target should move.

The TrueBeam series is known for its extraordinary precision and flexibility in pinpointing tumors with the lowest exposure to surrounding healthy tissues. It delivers radiation with a highly exact setup and very tight dose margins.

Calypso improves TrueBeam’s clinical advantage of extraordinary preciseness and accuracy. As a result, patients may experience fewer side effects. The current TrueBeam linear accelerator at Torrance Memorial is used primarily to treat brain tumors, cancer of the oral cavity and throat, and prostate cancers. It is designed to treat a very limited volume. The new TrueBeam will expand the ability to treat all types of tumors.

The Henry L. Guenther Foundation, the provider of the grant, is a private charity foundation dedicated to preserving and enriching the benefits of California residents, primarily those in Southern California. One of its top priorities is expanding medical services. Supporting Torrance Memorial with this latest advancement aligns perfectly with the foundation’s mission.