Chapter 18:  Research at the Proton Therapy Center; the Future

Chapter 18: Research at the Proton Therapy Center; the Future

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Dr. Cox notes that the Proton Therapy Center project was started in May 2003. Since 2006, when the first patient was treated, 4400 patients have been seen, with virtually all patients involved in research studies. Dr. Cox explains that there is a master protocol for studying increasing dosages and the degree to which normal tissue is spared. Specific protocols have been created to compare proton therapy and intensity-modulated radiation therapy on non-small cell lung cancer and for cancer of the esophagus. Next Dr. Cos explains the reasons why individuals question the value of proton therapy. Some are anti-technology. Some admit that it looks valuable on paper, but question whether the effects are real; some say that, in principle, there is value, but there are too many technical uncertainties to warrant going ahead with it. Others accurately state that no randomized trials have been conducted to definitely prove that proton therapy is superior to x-rays. These studies are underway now. Dr. Cox says that the main benefits are fewer side effects for the patient. In some cases physicians are able to deliver higher doses of radiation, which may result in better tumor control. Dr. Cox says that all of these objections make it difficult to get papers accepted in journals so good results can be demonstrated.

Dr. Cox affirms that the Proton Therapy Center has been very successful. The Center is also in the process of expanding uses for patients, so proton therapy will be part of treatment for many diseases and stages of disease. He anticipates that eventually 20% of MD Anderson patients will be treated with proton therapy. He explains how patients are identified for proton therapy (curative uses, rather than palliative). The Proton Therapy Center will be upgrading certain functions, taking advantages of developments Hitachi has recently made.

Dr. Cox observes that the regional care centers have not referred as many patients for proton therapy as he would have expected and that they would like to treat even more patients. As the segment closes, explains that the original investors pulled out of the project and MD Anderson owns 51% of the interest in the Center.

Identifier

CoxJ_03_20130423_C18

Publication Date

4-23-2013

City

Houston, Texas

Topics Covered

The University of Texas MD Anderson Cancer Center - An Institutional Unit; Overview; Definitions, Explanations, Translations; The Researcher; The Clinician; Building/Transforming the Institution; Multi-disciplinary Approaches; Growth and/or Change; Obstacles, Challenges; The Business of MD Anderson; Discovery and Success; Technology and R&D; Devices, Drugs, Procedures; Beyond the Institution; Controversy; Understanding Cancer, the History of Science, Cancer Research; The History of Health Care, Patient Care; The History of Health Care, Patient Care; Patients; Patients; Discovery and Success

Transcript

James D. Cox, MD:

So we ramped up. We started in the—started building in May of 2003 and treated our first patients in May of 2006. We have now treated approximately 4,400 patients, and we have treated over 1,000 with the scanning beam. And still there is hardly—you know—there are only a handful of patients that have been treated with this scanning beam any other place.

Tacey Ann Rosolowski, PhD:

So I assume—I mean are all of the patients—or the majority of patients who are receiving treatment involved in some sort of study?

James D. Cox, MD:

Uh-hunh (affirmative). Yes.

Tacey Ann Rosolowski, PhD:

And what kind of studies are you doing?

James D. Cox, MD:

There are several. One is in—basically they are studies of trying to increase the dose or deliver the same dose to the tumor while sparing normal tissues and documenting the degree to which you are sparing normal tissues. So we have a master protocol that takes all of those patients into account, and then we have discrete specific protocols for various components. We are doing the only studies comparing proton therapy and IMRT. We have a protocol that we started in 2008 that is nearing its completion that is for non-small cell lung cancer, and then we have a relatively recent protocol within the last year or so comparing IMRT and protons for cancer of the esophagus, and then we have a new protocol—a new protocol that is being developed for the RTOG, which is also asking that same question—protons versus IMRT.

Tacey Ann Rosolowski, PhD:

So this is still—since the number of patients is still pretty small, these must be fairly small studies.

James D. Cox, MD:

Right. They are. I mean—

Tacey Ann Rosolowski, PhD:

Are these all MD Anderson-based or are you collaborating?

James D. Cox, MD:

The one with—the only randomized study the IMRT versus protons that is in conjunction with Massachusetts General Hospital. And then there are some other small studies with Mass General that involve radiating the liver, children—various tumors in children, and the base of the skull.

Tacey Ann Rosolowski, PhD:

How long do you think—well—what is—is there a controversy right now about the value of proton therapy?

James D. Cox, MD:

Oh yeah. Big.

Tacey Ann Rosolowski, PhD:

And what is that based on? What is the conversation about?

James D. Cox, MD:

Well—turn your recorder off and let me— [The recorder is paused.]

Tacey Ann Rosolowski, PhD:

All right. So we are recording again.

James D. Cox, MD:

I think there are several reasons why people object to proton therapy. There is one group of people who are anti-technology. My wife, Ritsuko, ran into one in India when she was there at a meeting. A guy from England who simply said it is unnecessary, but then he said—you know—and IMRT is unnecessary, and he went on and on. Apparently none of the current technology seemed to be worth anything to him. So—okay—I mean if you are starting from that point I do not have much to say. There is another group that says, “Well—it looks good on paper in the computer, but how do we know it is real?” Well—we make actual measurements—our physicists make actual measurements for every patient before any treatment is given, so we know it is real. Plus we have examples of human dosimetry that have shown that it is also real. And so that does not hold water, although—again—there are people who believed that, and in this whole thing there is a lot of belief. Now the one thing that they can say which is accurate and is not believed is that proton therapy has never been shown in a prospective randomized trial to be better than x-ray therapy. And they are right. I mean—we are doing those studies now, and people have not done them before, and eventually those studies will be done and completed. But—and those are kind of purists, but they are right; there has not been any demonstration with prospective randomized comparisons.

Tacey Ann Rosolowski, PhD:

What are the preliminary findings from the studies that are being run now?

James D. Cox, MD:

Well—we are having fewer side effects.

Tacey Ann Rosolowski, PhD:

Is that the main area of benefit? Or are there—?

James D. Cox, MD:

Well, in some cases we are giving higher doses and still having fewer side effects, and we think that that will translate into better tumor control, and the side effects are—you know—especially important for children. I mean—my gosh—if you radiate any structure in a child—any growing structure—and all tissues in children are growing by and large—you run the risk of damage that is permanent and progressive. So anyhow those are the main—oh—and there is a third argument or fourth argument—whatever it is—that says okay, we understand in principle the value, but there are too many uncertainties in the physics and the dose distribution and the accuracy and all of this—too many uncertainties to be able to adopt this at this time. Now hiding behind that in many cases is a viewpoint that we are either not ever going to have proton therapy, or it is going to be so many years that we are going to have to be using x-rays for a very long time. And so there is the naysayer from the point of view of we won’t be able to have that. And—again—it has made it difficult in several areas. It has made it difficult to have papers accepted in journals because one or another reviewer may come at it from any one of those directions that says—you know—this is just not true or not valuable, and it has been a surprise because people who say, “Well—we need data,” and then you go to publish data and they do not want to accept the data, and the data is never perfect. I mean—it is always more fragmentary and incomplete than you would like it to be. But in the meantime the body of data will build if there are publications that can be looked at. So—anyhow.

Tacey Ann Rosolowski, PhD:

That is surprising. Yeah. So what do you foresee in the future for the research and for the Proton Therapy Center?

James D. Cox, MD:

Well, I think—the Proton Therapy Center here is being very successful. One of our main goals was to expand the indications for proton therapy beyond those that had been already investigated in the physics research facilities years ago—expand into other areas where protons would be valuable. And this could be in the head and neck, in the brain, of course children, in the abdomen where it is not used very much, possibly in the pancreas, certainly for the liver, and maybe for the rectum. So I think proton therapy is going to establish a place for the treatment of many diseases or many stages of disease so that it will possibly occupy as much as maybe twenty percent of all the patients that are treated with radiation therapy. It is not going to ever be close to one hundred percent. So—and I think there is enough recognition of that value throughout the world now that it is just—you know—the development of proton centers is going very rapidly.

Tacey Ann Rosolowski, PhD:

So how do you determine which patients will receive proton therapy?

James D. Cox, MD:

Well, one are these sort of protocols that we have developed where we have thought ahead which patients would—for which patients it would be valuable. And that is brain, children, lung, head and neck, esophagus, and with this we know what specific normal tissues we are trying to avoid, what side effects we are trying to avoid, and that is the goal. And we also know that there are some types of patients that we are not ever going to treat with protons. We are not going to do total-body radiation. We are not going to do whole-breast radiation in place of mastectomy. We’re just not. And we are not going to use it by and large for just palliative care. It’s not that we will never use it for symptom relief, but by and large it is to be used to treat patients with curative intent. If it’s to be used for palliative care, it’s to give a very high dose in an area where they are surrounding normal tissues that are really worrisome.

Tacey Ann Rosolowski, PhD:

So do you see the center expanding, or how do you—where do you see it going?

James D. Cox, MD:

Oh I think it will—I think it will stay pretty much the way it is probably for another year or two because there needs to be upgrades of certain things. Hitachi has made further developments as they have developed facilities for other institutions, so they have made progress in areas that we are interested in. We can do a better job of combining imaging with the proton therapy, which we do not have the best imaging in the room that we would like to have, and so we need to get that developed. But there are plans and a way to do that. So I think it will continue to develop and—

Tacey Ann Rosolowski, PhD:

Now, in terms of the relationship of this center with other departments and services at MD Anderson, do you find that you work well with people—identifying patients of theirs that might be—

James D. Cox, MD:

Yeah.

Tacey Ann Rosolowski, PhD:

And so that communication process has been pretty smooth?

James D. Cox, MD:

In general that has been quite favorable. We have not had—yeah—that has been quite favorable.

Tacey Ann Rosolowski, PhD:

And I’m sure that will help a lot in feeding patients into your study—

James D. Cox, MD:

Oh—it does.

Tacey Ann Rosolowski, PhD:

Right.

James D. Cox, MD:

It does help a lot.

Tacey Ann Rosolowski, PhD:

Yeah. Is there anything else that you would like to say about—

James D. Cox, MD:

Where we have not had great success is recognition in the regional care centers of the value of proton therapy, so we get very few referrals from the regional care centers.

Tacey Ann Rosolowski, PhD:

What do you think that’s about?

James D. Cox, MD:

I don’t know.

Tacey Ann Rosolowski, PhD:

That’s interesting.

James D. Cox, MD:

I don’t have a good explanation for that. We have one person in Clear Lake who sends us patients—not high volume—but sends us patients on a regular basis, but she is the only one.

Tacey Ann Rosolowski, PhD:

Who knows—that is interesting. Is there anything else you would like to say about the Proton Therapy Center? Or the process of developing it (both speaking at once)?

James D. Cox, MD:

You know—I think it’s been—well what has happened over the past few years is that the original investors have pulled out there—the financial commitments to them have been completed. I don’t know what the financial breakdown of the various components of support for the Proton Center, but it is my understanding that there are Chinese investors that are involved in the last year, and there are—and MD Anderson now owns actually the majority. I mean—it has—I think it has fifty-one percent interest, and I believe that was bought out from Hitachi. So I think it is going okay. I think it is maybe not—we are not treating as many patients as they would like to see, but I think that will fluctuate over time.

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Chapter 18:  Research at the Proton Therapy Center; the Future

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