Ten years ago every surgery resulted in a big scar, a big cut, and now everything is done through as minimal a hole as you can get. Is this right?
Gloria Hwang: That's true. There are certain things that surgery is absolutely great for. Surgery is considered the gold standard for a lot of procedures including certain kinds of tumors. In some cases surgery is too dangerous, or in areas that are inaccessible by surgery, or in patients who just don't want to have a big cut and have a nice small enough tumor you can actually get away with treating those tumors with just a little needle poke in the skin. I think that's great for the patients, especially if they have conditions in which they really have no other options. I think we offer a great benefit to those patients.
I've always heard of pancreatic cancer is a death sentence because it's so hard
to treat that area because it's very deep. Is that correct?
Gloria Hwang: Exactly, pancreatic cancer is one of the toughest cancers that the medical community faces. Their chemotherapy options are pretty limited now. People are working very hard to find new therapies that we hope are going to be more effective. So right now it's a big team approach to find the best way to control pancreatic cancer. So, the members of the team are usually the oncologist and a radiation oncologist who can treat the pancreatic site and if there are tumors that go to the liver then that's where someone like me steps in. We can actually treat tumors in the liver with ablation therapy and gain control in that location. And hopefully buy patients some time where they may not need so much chemo.
Could you explain ablation therapy?
Gloria Hwang: It's actually amazing when you think about it. People have basically taken needles and found a way to make them so that they can kill cells around the tips of the needles. And there are a few ways that we do that. There's radio frequency ablation where you turn the patient in to a circuit and you have tines coming out of these needles and the vibration of molecules around them cause the tissues around them to cook and die. Then there's microwave ablation which is a newer technology where someone actually takes a microwave antenna and sticks it to the end of the needle and sends out waves which allows tissue to cook often faster and larger areas than radio frequency ablation. And then you have cryoablation where people will actually send pressurized gases through these needles and allow a big zone of freezing that can also kill tumors.
And all of this is done with just a pinhole approach?
Gloria Hwang: Exactly. Sometimes one, sometimes a few of them, but really at the end of the case our patients come out with just Band-Aids on their skin from the needle holes.
So are the patients cured of their cancer after this?
Gloria Hwang: I think cure is a difficult word. When we finish the case our goal is to get 100 percent of the tumor that we target. This tumor can be in the liver or the kidney. The lungs actually are a good place for ablation therapy too. But patients always get a follow up for their cancer with imaging, because cancers can come back either because a little cell has survived in the area we treated or because a cell has gotten to a different part of the body. So we always want to make sure that staying ahead of that.
So when you're doing this can you see the cancer basically die in front of you?
Gloria Hwang: You can actually, for microwave ablation. What's really great is that I use a CT or ultrasound to get my probes into the patient and then I actually use ultrasound to watch the heating happen. When the heating in the liver happens you actually can see gas bubbles, and those bubbles are a pretty good approximation of where the cooking zone is. If you do CT you can actually see a little halo in the lungs that also is a pretty good indication of where the cooking is happening. And so I try to pinpoint the tumor with CT or ultrasound and then I watch the cook zone until it looks like its engulfed the tumor and has a good margin around it.
Now how hot does that get?
Gloria Hwang: It can get pretty hot, above boiling in some cases. The
temperature is actually measured along the protract, so of course temperature drops as you go further away from the needle. I've seen temperatures up to 112 degrees with microwave ablation.
Is this safer than like say radiation?
Gloria Hwang: I think it's different and complimentary. There are different ways of administering radiation and some organs tolerate it better than others. In the liver you can do targeted radiation therapy; they call that saber. And you can also do targeted ablation in some locations. Like very high up on the dome of the liver, it may be safer to do the targeted radiation therapy. In
other areas, like if you have a very large mass at a very accessible location then you do the ablation therapy with our technique. It's a one stop shop and you can see then and there whether you think you've gotten the whole tumor.
Is it safer than say radiation, where there's a lot of risk of damaging other
Gloria Hwang: There is a risk of damaging other tissues with radiation so for everything there's a plus and a minus. With chemo you have the toxicity of the chemo to the rest of the body. The way they do it their radiation is really focused on that central spot, but you have a drop off of radiation that surrounds that spot. So the surrounding organ does get a dose and each part of the body can only really tolerate a certain dose before it has toxic effects, or begins to affect the functioning of that organ. And for our therapy you pretty much kill the area around the tumor. But you have to be careful because you have to be really careful that you don't injure the things surrounding the
Tell me a little bit about Gwen.
Gloria Hwang: Gwen is a remarkable patient. When she first came to me, she had cataracts and she could not be on chemotherapy and get cataract surgery. She already had metastatic pancreatic cancer and we knew that her tumor had spread from her pancreas to her liver and so she could not undergo surgery as a cure for that. She also had received radiation to her pancreas and so the only things she had left to deal with were these tumors that were in her liver. And she really, really wanted to be able to drive again and had to be able to stop her chemotherapy. They were afraid if they stopped that for too long, the cancer would just go out of control. So at that point I was asked to treat those tumors in her liver so that she would have a safe window without cancer so that she could get her cataract surgery. We did that and she had imaging and the tumors looked treated; so she had her cataract surgery and that was fantastic. And then unfortunately some more tumors showed up and so we've been treating those. So I've been working with her for, I think it's almost two years now. It's been a long time.
So are you treating the second round of tumors with ablation as well?
Gloria Hwang: I did, I treated her tumors for three rounds now actually with ablation. And she's also had radiation to some of the tumors that were not accessible to me. So she's actually had a full complement of treatments.
Does she just go home that same day?
Gloria Hwang: We kept her overnight. I usually keep my patients overnight just
to make sure they're comfortable and she's always smiling in her room afterward, but we want to make sure if there is any soreness in the liver. Some people get nauseated from the anesthesia or the medications that we give them to treat any discomfort. We want to make sure that patients are comfortable and able to eat and walk and go about their lives before we send them home.
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