Higher Dimensions of Cancer Care

Scripps Cancer Center is committed to providing all our patients with innovative technologies to fight cancer. One example is radiation therapy, a discipline where precision saves lives. 

With support from committed philanthropists, Scripps has recently added several Varian TrueBeam linear accelerators — one of the world’s most sophisticated radiation oncology technologies — to our therapeutic toolkit. 

“The TrueBeam is a state-of-the-art linear accelerator,” says Norbert Kased, MD, radiation oncologist, Scripps Clinic. “If I were to design something for my patients, this is the machine I would make.”

The TrueBeam defines precision, providing an extra level of care for patients with breast, lung, prostate and other complex cancers. This advanced radiation oncology technology can tightly conform its beams to eradicate tumors, while sparing healthy tissue. The TrueBeam is the newest iteration of image-guided radiation therapy (IGRT), which can follow moving targets, such as lung tumors that shift as a patient breathes. It also provides leading-edge capabilities to help patients with difficult-to-treat cancers.

“The new accelerator provides high-dose ablative intracranial treatments for patients whose cancer has spread to their brain,” says Thomas Buchholz, MD, medical director, Scripps Cancer Center and radiation oncologist, Scripps Clinic. “Often these patients require brain surgery. Bringing in this technology provides our patients with better outcomes and new hope.” 

The TrueBeam is in use at Scripps Cancer Center on John J. Hopkins Drive on the Torrey Pines Mesa, Prebys Cancer Center at Scripps Mercy Hospital and Scripps Clinic Radiation Therapy in Vista. 

The new machines raise the bar for cancer treatment. In addition to precisely targeting tumors, the TrueBeam is four times faster than previous radiation oncology machines. In other words, many patients will spend less time being treated.

*This article was published prior to Prebys Cancer Center’s opening on September 13, 2021.

The first radiation machines lacked the refinements that make current technologies so much safer and more effective. Radiation from these earlier instruments successfully destroyed tumors but could also damage healthy structures. As a result, radiation oncologists had to use lower doses to avoid side effects.

A revolution in the early 2000s changed how radiotherapy is delivered. The first step was intensity modulated radiation therapy (IMRT), which shapes beams to conform to the three-dimensional shape of tumors.

“IMRT allows us to sculpt the dose around the cancer and keep it away from normal structures that don’t have cancer,” Dr. Kased says. “That was a game changer.”

Later, image-guided radiation therapy (IGRT) took the fourth dimension into account: time. No matter how stationary a patient might be, they still have to breathe, which can move tumors during therapy. IGRT uses CT scans, conducted before and during treatment, to ensure proper aim.

“In the past, we were often limited by a tumor’s proximity to a noncancerous organ, so we had to reduce the radiation dose accordingly,” says Dr. Kased. “Now, with more precise technology, we can escalate doses, which improves our ability to destroy the cancer. I have many patients who are free of cancer and live completely normal lives. It’s remarkable, and it’s largely attributable to these advances.”

The TrueBeam takes this technology to the next level. Its radiation precisely conforms to tumors’ irregular shapes, and motion management systems ensure the beam follows the target wherever it goes. Scripps Cancer Center has also upgraded its CT capabilities to better plan treatment.

“We conduct four-dimensional CT scans that give us the tumor’s exact location,” says Ray Lin, MD, medical director, radiation oncology, Scripps Cancer Center, and radiation oncologist, Scripps Clinic. “In addition to the 3D axes, we track how it moves with respiration in real time, which is particularly important with lung and liver tumors.”

All these technologies support one goal: providing the most precisely targeted therapy to reduce potential side effects from off-target radiation. Equally important, these advanced instruments allow patients to complete their treatments in fewer visits.

“We used to treat many cancer patients in six to seven weeks,” says Dr. Lin. “Now, for certain patients, we can treat them in one to four weeks as a result of this added precision.”

Recent advances in systemic therapy, such as chemotherapy and immunotherapy, have made radiation oncology even more vital. 

“As systemic therapy has become more effective, we have played an increasingly important role,” says Dr. Kased. “In the past, when systemic therapy was less effective, patients had cancer everywhere and local treatments were less important. Now, a patient might have only one or two areas in their body that aren’t responding to the systemic therapy, and we can eradicate those bad actors.”

Radiation therapy has also been shown to support immunotherapy. As radiation kills cancer cells, they release antigens into the body, priming the immune system to better attack tumors. 

“It’s called the abscopal effect,” says Dr. Lin. “Researchers noticed that, after radiation treatments against tumors in one part of the body, tumors in another area would start to shrink. Now we believe this could be used to make immunotherapies even more effective.”

As radiation, surgical and medical oncology advance, their common goal is to transform even the most aggressive cancers into more easily managed chronic diseases.

“It’s an exciting time in oncology because until recently, we generally made slow, incremental improvements in care,” says Dr. Kased. “Now I have patients who had metastatic cancer and are now long- term survivors, which was less common with prior traditional treatments.”