Optimizing the Staging of Biliary Tract Cancers

Transcript:

Milind M. Javle, MD: Dr Koay, Dr Rocha earlier mentioned various terms for this cancer, which is sometimes confusing. It’s called cholangiocarcinoma, bile duct cancer, gallbladder cancer, biliary tract cancer. Add to those the different staging systems. How so you rationalize this when discussing it with the patient? Sometimes patients really don’t know what they have. They ask, “Do I have cholangiocarcinoma, or do I have bile duct cancer?” They’re colloquially referred to as gallbladder cancers, though clearly, it’s not.

Eugene J. Koay, MD, PhD: It can be quite confusing for patients, their families, and friends. Physicians also can sometimes get these things confused. There’s a lot of terminology. The extrahepatic cholangiocarcinomas, the gallbladder cancers, and the intrahepatic cholangiocarcinomas are generally grouped as biliary tract cancers. They’ve been treated as such in clinical trials, as just 1 group. Although they are, as Drs Rocha and Javle have mentioned, distinct diseases. This is probably what has contributed to the confusion about how you classify them.

When it comes to describing these, it is where they begin. The extrahepatic cholangiocarcinomas begin in the bile duct that is outside of the liver, so extrahepatic, outside the liver. That starts at that perihilar area where the common bile duct begins to branch. That’s the way extrahepatic cholangiocarcinoma is classified anatomically, and it goes down to where it meets with the pancreas in the bowel. The intrahepatic ones are inside the liver, the ones that are inside the bile ducts within the liver. Then of course gallbladder cancer is within the gallbladder.

When it comes to the staging of this, and Dr Rocha can probably speak to this in terms of the surgical staging as well, these have their own different staging systems. The AJCC [American Joint Committee on Cancer staging system] is the commonly referred way, the tumor, nodule, metastasis TNM staging. Each one of those has their own distinct way of describing their TNM staging. These are generally based on how big the tumors are, how much they infiltrate or how large they are in the local vicinity of the tumor, and how many lymph nodes may be involved. Then whether there’s metastasis, either within the liver or outside the liver. Those are the things that describe the overall stage as well as discreet stage in terms of TNM staging that each of those 3 diseases has.

When you think about this clinically, you’re also thinking about whether that patient has localized disease, is it something that can be surgically resected or not? Those 2 general classes guide early intervention as far as therapy is concerned. Do you do surgery up front, or chemotherapy? Is radiation or something else toward the liver indicated? That clinical decision is tied to the TNM AJCC stage overall, but really it’s a question of is surgery an option for that patient or not. That’s clinically how we think about it and approach it whenever we start talking to patients. I’m curious to see what Dr Rocha says here.

Flavio G. Rocha, MD, FACS, FSSO: I think that’s spot on. I would add that as a surgeon, we are very much reliant on the quality of the imaging. The radiologist plays a big piece here. Again, the more specialized radiology you have, the better. Dr Javle mentioned liver-specific scans. We typically rely on a good 4-phase liver CT scan, where you have an arterial phase, a portal phase, and a delayed phase, because the tumors will light up differently. We know that, for example, in hepatocellular carcinoma [HCC] we typically make the diagnosis just based on imaging. Cholangiocarcinoma looks different on imaging than hepatocellular carcinoma.

The important part for me, besides what Dr Koay mentioned as far as metastases and lymph nodes, is what’s the relationship of the tumor to blood vessels. As a surgeon, I have to be able to remove one side of the liver or the other, remove the bile duct, or remove the head of the pancreas. The tumor has to be free from these critical structures, like the portal vein, the hepatic artery. Those can be very important for us to look at together.

I think the evolution in MRI technology has also been amazing, especially to detect things like Dr Shroff mentioned, the satellite tumors that are small perhaps by CT scans. Now we’ve also used things like PET [positron emission tomography]-MRI, where you’re getting the very fine images from the MRI coupled with the functional imaging of the PET, to see if these findings are metabolically active and potentially a tumor. As you’re hearing, this is a very complicated disease. You really need multidisciplinary management, which includes many others besides the 4 of us here.

Milind M. Javle, MD: Yes. I think Dr Rocha touched on a very important point, imaging is key. I have to say that there are certain institutional preferences. Some are more MRI-based. For us at The University of Texas MD Anderson Cancer Center, we do a CT scan, a multiphasic scan, which shows for instance early enhancement and rapid washout, which would be like HCC, or delayed enhancement, which would be more like intrahepatic cholangiocarcinoma and metastases. We often see patients who have had CTs, PETs, and MRIs, and it’s an unnecessary overutilization of resources. I think a good quality imaging of 1 kind is probably enough in most instances.

Transcript edited for clarity.