Proton Therapy on NPR's "Fresh Air" with Terry Gross:
An Interview with Dr. William Hanson of UPENN

Fresh Air with Terry Gross is an Award-winning weekday magazine show and one of most popular programs on National Public Radio. About 4.5 million listeners tune in across the country as well as in Europe on the World Radio Network. Here's what Dr. Hanson, author of a new book noted below, said about proton therapy on November 17, 2008

GROSS: One of the largest and maybe most impressive and most promising technologies that you write about in your book is proton-beam therapy. Tell us a little bit about what that is.

DR. HANSON: Well, one of the early physicists recognized that protons had a special characteristic, that they could be trained, in effect, to drop or release their energy at a very localized place in space given the right set of characteristics. And this same physicist recognized that that property was a way in which to have energy released that would kill tumors or cancers in a very localized fashion, so that you could train a beam of protons to enter the human body and not release any of their damaging radiation until they were inside of a tumor.

So, let me compare that to traditional radiation, which we are much more familiar with, where beams of radiation are trained on a tumor, but the radiation is released all the way along the path. So there's damage to the skin over the tumor. There is damage to the organs between the skin and the tumor, and you try to concentrate the damage in the tumor, but there is damage to all the tissue surrounding the tumor.

As you may be aware, one of the elements of the Hippocratic Oath is that a physician is primarily directed not to do harm to their patient, and the Latin term for that is primum non nocere. We do damage to patients all the time with our medications, with radiation and the like.

GROSS: Oh yeah.

DR. HANSON: And it's a recognized risk-benefit ratio, in effect, that you take the risk of damaging normal tissue in order to kill the malignant tissue. The proton beam approach is so precise that we can train a beam of protons on a tumor millimeters in size or even a millimeter in size that may be located in somebody's eyeball, kill that tumor, and leave sight intact. That is not a possibility with traditional radiation.

GROSS: That sounds really amazing. How close are we to actually integrating that technological medicine into everyday practice?

DR. HANSON: Well, we're doing it. I mean, proton-beam therapy is a therapy that's been in existence for a while now. We're getting better at it, and the devices are getting more precise, and the targeting is getting better because we can now use things like a CAT scan or an MRI to very precisely localize the tumor, which then allows us to very precisely train the beam of protons.

But these sorts of technologies are entering medicine at a pace that - I don't think most of us recognize that therapies like proton-beam therapy or technologies like robotic surgery or computerized artificial-intelligence applications, these technologies are diffusing into medicine at a rate and a pace that I think most of us are unaware of, and are going to drive us to places that, without some thought, could be very good or could be very problematic.

GROSS: So, what kinds of tumors is the proton-beam therapy best suited for?

DR. HANSON: Because the prostate is a wallet-sized organ that lies between some other critical structures. Included in that are those of urination, defecation, and sexuality. So one of the big concerns that people have with the variety of different current treatments for prostate cancer is, will I be able to have sex? Will I be able to be continent and not urinate in my underwear? Will I be able to have fecal continence? These are very meaningful questions, and people struggle with the different treatment alternatives based in large part on the answers to those questions and how they prioritize these things.

GROSS: But with proton-beam therapy, you go directly to the tumor, and the other tissue isn't going to be affected. So...

DR. HANSON: It's a very precise way...

GROSS: It's much less risky.

DR. HANSON: Yes, it's a very precise way of treating that cancer with minimal to negligible damage to the surrounding important tissues.

GROSS: If you're just joining us, my guest is Dr. William Hanson. And he has written a new book called "The Edge of Medicine: The Technology that Will Change Our Lives." He's a professor of anesthesiology and critical care at the University of Pennsylvania. Let's take a short break here, and then we'll talk some more. This is Fresh Air.


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