By Natalie Chang
While Scott Yanke was being treated for a rare and serious form of cancer, he was skydiving a lot.
He was being treated at MD Anderson Cancer Center in Houston for dedifferentiated liposarcoma, a cancer that forms from the body’s fat cells. His tumor was retroperitoneal, meaning it was in his abdomen, pressed right up against his intestine. It was surrounded by critical organs like his kidney, ureter, and pancreas, which made it difficult to treat, especially with radiation. Traditionally speaking, the side effects that come with radiation therapy can be debilitating and chronic, whether they are nausea and digestive problems, fatigue and weakness, difficulty breathing, skin blistering…the list goes on. And because of Scott’s tumor’s location, the side effects would have likely been quite severe, since the organs that surrounded it are very sensitive to radiation.
And yet, throughout his treatment, he was indoor skydiving “a whole bunch,” he says.
The reason that he felt so good—in fact, he even went back to volunteer firefighter training just six weeks after his treatment finished and he had surgery—had everything to do with the specific kind of radiation therapy he received, a relatively new and innovative treatment called proton beam therapy.
“Proton beam radiation is just a more accurate way of delivering radiation,” says Sam Yoon, MD, Chief of the Division of Surgical Oncology at Columbia University Irving Medical Center and the doctor who treated Scott’s cancer. “Proton radiation uses protons, which are particles. And the way that the particle energy is delivered is that when the particle leaves the machine, the energy is about the same when it leaves the machine as it is when it hits the target. And then, you can stop a proton immediately beyond the tumor. So we generally say that there's less entrance dose and almost no exit dose of radiation.”
Traditional radiation, which uses photons, has to factor in the energy the photon loses as it travels away from the machine and towards the tumor being treated. That means that as the photon enters the body, it’s delivering high doses of radiation to whatever it passes through on its way to the tumor, and still delivering radiation as it leaves the tumor, which is what leads to the negative side effects we associate with radiation treatment.
That’s one reason why Dr. Yoon feels strongly about using proton beam therapy when it comes to tumors located in sensitive areas—it can minimize damage to important organs, meaning patients undergoing proton beam therapy can feel good enough to skydive, like Scott. But more than that, he also has seen proton beam therapy be more effective in controlling tumor recurrence.
“With surgery alone, local recurrence rates are about 50 percent or even greater,” Dr. Yoon says. “And traditional radiation therapy techniques have had a difficult time in reducing that local recurrence rate. Using the technology of the proton beam machine with novel techniques to deliver radiation, our local recurrence rates are about 10 percent in five years.”
Lowering recurrence rates, he points out, means lowering death rates. In other words, using proton beam therapy on patients with tumors in sensitive locations could save their lives.
So why aren’t we using proton beam therapy left and right?
For one thing, it’s still very expensive to build and operate proton beam machines. There are only a couple dozen operating machines in the United States, and the treatment method is still new enough that many doctors and insurance companies still need convincing. Dr. Yoon has made it his personal mission to make proton beam therapy a more mainstream and promoted form of treatment for certain rare cancers.
“It’s still a pretty significant minority of people who elect to have this approach. And it’s been really frustrating for me to try to convince people,” he says. While some patients do their own research and actively reach out to Dr. Yoon and other proton beam experts, he finds that other doctors rarely recommend proton beam therapy even to patients whose cancers are in areas sensitive to radiation.
Scott, who owns a radiation shielding technology company, was fortunate because his work had already helped him form many connections in the medical field. After he received his diagnosis of dedifferentiated liposarcoma, he reached out to those networks to get recommendations and referrals—and Dr. Yoon was one of the first names that came back.
“I ended up with Dr. Yoon because he had the first available appointment,” Scott laughs. “That was just dumb luck.”
It was more than just lucky—it probably led to the positive outcomes that Scott has experienced so far. “I'm only 47 years old. The typical person with liposarcoma has about 10 years' worth of surgeries and a very shortened life expectancy,” Scott points out. “Dr. Yoon's treatment plan was the one that gave me the best shot of having a one-and-done…. When he laid out the results that he had seen, and I realize this isn't a peer-reviewed article, but it's his own results from his own patients, it was a no-brainer.”
But even when patients do successfully connect with a proton beam expert and elect to have the treatment, ensuring that it’s financially feasible is yet another hurdle to clear. “It was a battle to get insurance to cover it,” Scott says. “I was on my third denial, but I felt so strongly about it that I called my company comptroller, and on the day that my insurance finally approved it, she had just cut a check to send to MD Anderson for me to get the proton therapy. I was willing to spend the money personally to get it if insurance wasn’t going to cover me. That’s how strongly I felt about it.”
Why are people so hesitant to get on board? Because proton beam therapy is a relatively new, relatively expensive, and very specific form of treatment, there just isn’t that much data available on its efficacy with large sample sizes. Dr. Yoon has published articles and trials showing how much proton beam therapy can reduce tumor recurrence rates, but finds that they don’t get much traction because there aren’t that many patients getting the treatment.
He’s also trying to make waves in a medical area that has gone with established and proven forms of treatment for a long time. Cancer treatment has advanced far enough that it largely consists of tried-and-true “recipes,” as Scott calls them, that doctors are comfortable with and believe to be safe and likely to work.
“This is a small field. I get the sense that if you're at the top of the field and you have been treating your patients one way, and you think that you've been treating them the best and someone here tells you, ‘Look, my results are so much better,’ it's natural for people to be skeptical,” Dr. Yoon says. “But to be honest, proton beam has been something I’ve been doing throughout my career, and I believe it works.”
Dr. Yoon is currently waiting on results from a phase II trial that will provide more data on the efficacy of proton beam therapy. And while he may be frustrated, he’s also encouraged by the increasing number of proton beam machines being built; by the other possible applications of proton beam therapy for spinal tumors, heart tumors, and tumors in children; and by the personal journeys of the patients he’s treated, like Scott.
“I feel awesome,” Scott says, laughing. Since he finished treatment less than a year ago, he and Dr. Yoon are still waiting to see the long-term outcomes over the next few years. But he already feels optimistic.
“I believe my long and healthy future is 100 percent because of Dr. Yoon and his treatment plan to include proton therapy,” he says. “I'm too young to die of cancer, and I will die of old age now because I was fortunate enough to run into Dr. Yoon.”