Precision Medicine: A New Frontier for Advanced Cholangiocarcinoma - Episode 3
Ghassan Abou-Alfa, MD, MBA: Let’s dissect a few other points, Martin. Whenever patients come—and I’m sure we all kind of witnessed the same thing—they’re always driven by numbers and figures. One of the things that people depend quite a bit on is, “What’s my cancer number?” which is a certain tumor marker. Any value for CA [cancer antigen] 19-9, CEA [carcinoembryonic antigen], AFP [alpha-fetoprotein] in that disease?
Martin Gutierrez, MD: It’s a good point because actually we put together what we discussed a second ago. I’m going to go back to the community. Actually, trying to dose cholangiocarcinoma in the community is still quite difficult. Even though we have the molecular testing and we’re moving forward for the intrahepatic portion of the disease, the regular pathology only has CK7 really, and I still have to decide, “Well, is this a cholangiocarcinoma or not?” But CK7 is positive in other diseases. This is when the biological markers like CA 19-19 and CEA may have some value added to it. Plus, radiology would be added to it. The CA 19-9, unfortunately, still is not specific enough to establish the diagnosis. It has to be in the appropriate context and in an appropriate level to be able to establish that diagnosis.
Ghassan Abou-Alfa, MD, MBA: I totally agree. Andrea, how often would you…We all check on tumor markers. Would you do it on every treatment visit for a patient, or at time of scans, or when patient wished to have it?
Andrea Wang-Gilliam, MD, PhD: Normally I would check it with every month or so, every 3 to 4 weeks with a treatment, but not necessarily that often. CA 19-9 is not very specific, so we likely observe the trend rather than just jump into the absolute change or the change of velocity. So patients do get a comfort. They don’t freak out with 1 really high number.
Ghassan Abou-Alfa, MD, MBA: Yeah. Well, personally, I don’t know. Do you do it more or less, Andrew?
Andrew Zhu, MD, PhD: I do it. I definitely agree with Martin and Andrea. I think that clearly it’s not specific enough.
Ghassan Abou-Alfa, MD, MBA: Fair.
Andrew Zhu, MD, PhD: The other thing that we need to point out is that for patients with biliary obstruction in the setting of rising bilirubin, the level can be falsely elevated. That part should be taken into consideration as well. But in the absence of any other more reliable or biomarkers, I do think that we should incorporate the use of CA 19-9, both in the diagnosis as well as the follow-up.
Ghassan Abou-Alfa, MD, MBA: Fair enough. What we heard so far is that cholangiocarcinoma understandably and biliary cancers altogether are really a big challenge in regard to diagnosis. Historically, we don’t have that many clues with regard to pathology. If anything, as we just heard from Dr Gutierrez, CK7, of course, would not be enough to delineate the disease. As such, it is dependent on the expertise of the pathologist at hand. Of course, pathologists who see more of that disease will be probably the right people to decide if this is intrahepatic or extrahepatic cholangiocarcinoma. Gallbladder cancer has some further delineation because of where it’s coming from anatomically. But I think what you heard from all of us is that there is a drive into more of the genetic makeup of those tumors that can really delineate it 1 way or the other to be a certain diagnosis—being intrahepatic, extrahepatic cholangiocarcinoma, or gallbladder cancer. We promise we’re going to talk a little more in details about that.
The last point that was brought up is that the tumor markers are really nonspecific. We heard a few different point of views on that. If anything, however, clearly because of the nonspecificity, it’s probably going to be delineated with something further than this. In general, if anything, doing it super routinely is not really required because we don’t know what to do with that. If anything, to connect it with some other findings, like, for example, the CT [computed tomography] scan—ie, doing it, for example, at the same time as a CT scan—will probably make a lot of sense.
Transcript Edited for Clarity