Even with new cancer medications, biological drugs and individualized gene therapy, radiation is still used in for a majority of cancer patients. Now, research brings radiation into sharper focus.
By Stephanie Soucheray
It’s a question Fang-Fang Yin has heard before.
“When I first started graduate school, people asked, ‘Will radiation be used 100 years from now? Fifty years from now?’” said Yin, a professor and director of radiation physics at Duke University. “Back then, everyone thought gene therapy would be leading us today in cancer treatment. But the fact is, radiation therapy is still used in 60 percent of all cancer treatments.”
Radiation was first used to treat and even cure cancer in the late 1890s, and was advanced under Marie Curie. Today it is used in many cancer treatment plans, especially for lymphomas. There’s been no real change in the fundamental idea of radiation for 70 years, but Yin said that quality assurance and imaging used to administer the treatment is advancing.
Because of its prevalence, and its inherent appeal to engineers, Yin presented his latest understanding of imaging and radiation therapy at the N.C. Biotechnology Center last week to the Eastern North Carolina Section of the Institute of Electrical and Electronics Engineers (IEEE).
The presentation was part of the Intellectual Exchange hosted by the IEEE that focuses on health care technology in the Triangle.
Radiation, along with chemotherapy and surgery, is one of the three main treatments of cancer. Like surgery, radiation is used to remove cancer cells at a specific site in the body, often the lungs, breast or even brain. But unlike surgery, successful radiation requires the calculations of physicists to figure out where to beam ionizing radiation to guarantee cancer-cell death.
Yin is not a medical doctor; rather, he’s one of the “invisible physicians” who treat cancer patients behind the scenes. Yin described the painstaking offstage work done by physicists for cancer patients who undergo radiation. Using protons, photons and electrons as high-energy radiation beams, physicists, and not oncologists, often direct treatment for radiation patients.
“We work with the oncologist and the technician to deliver radiation therapy precisely and accurately,’ said Yin. “You can have precision but not be accurate in delivering the therapy, and you can be accurate and not precise. But if you’re not both, healthy tissue surrounding the cancer can suffer.”
Take, for instance, someone with lung cancer. While the neck or head can be immobilized during radiation therapy, the lungs are constantly breathing. Patients can be instructed to hold their breaths, but even then exactitude is needed to make sure only cancerous cells are targeted. That exactitude comes from what Yin calls the “phantom patient,” an individualized treatment plan based on a person’s dimensions that reproduces the radiation therapy before it even begins. Yin called it “organ motion management.”
“The future is in imaging,” said Yin, as he showed several slides of radiation procedures to a few dozen engineers. More specifically, the future is in high-tech 4-D imaging that uses CT and MRI scans, among other modalities, to bring individualized treatments to patients.
The biomedical sciences are one of North Carolina’s most important industries, and the N.C. Biotech website estimates there are 129 companies in the Triangle that develop medical devices. But Yin said he does not have a relationship with any Triangle-area companies.
“That’s part of why I’m here today,” said Yin. “The Triangle has the financial resources, and the schools have the research. Hopefully, we’ll build a relationship between radiation imaging and the Triangle.”