This transcript has been edited for clarity.
Benjamin L. Schlechter, MD: Dr. Dib is the director of the Hepatobiliary Surgery and Living Donor Program at Beth Israel Deaconess Medical Center here in Boston, and a Harvard Medical School faculty member.
He was previously at the Pontificia Universidad Católica de Chile, a leading international institution investigating the role of liver transplant in colorectal cancer, among other diseases. Dr. Dib, before we move to our discussion, I’d like to hear a bit about your pathway to becoming a transplant surgeon. How did you end up working on colorectal cancer and liver transplants in this field?
Martin J. Dib, MD: Thank you so much, Dr. Schlechter. I am originally from Chile. I had an opportunity to come to Beth Israel Deaconess Medical Center after medical school and I did liver regeneration research at the transplant center. After that, I was lucky enough to match as a general surgery resident at Beth Israel Deaconess.
This is my alma mater and I was able to graduate as a surgeon here. You and I had some paths together. After graduating from Harvard as a surgeon, I was trained in liver transplant, abdominal transplant, surgical oncology, and hepatobiliary surgery at the University of Toronto.
I have been developing this passion for being able to transplant cancer patients and use organ transplant techniques to be able to do complex resections for cancer.
Dr. Schlechter: Let’s talk about the topic for today, which is liver transplant and colorectal cancer. I’ll be honest — this is not a very familiar topic for a lot of oncologists. There are a lot of details that I think are new to us as oncologists. We need to expand this conversation to get access to patients for this.
First and foremost, can you talk about some of the parameters for a resectable liver metastasis vs unresectable disease that would be an indication for a liver transplant?
Dr. Dib: I think this is a very interesting topic because liver transplantation for cancer is not new. Liver transplantation started in the 1960s when people started doing liver transplants for advanced liver tumors. The problem is that they were selecting patients who had very advanced — and poor tumor biology — tumors. The outcomes were not good.
It was only in 1996 when the Milan criteria started. Mazzaferro and colleagues, using strict patient selection, were able to do liver transplant for selected hepatocellular carcinoma patients. Having those excellent outcomes in selecting patients opened the field for what we now call transplant oncology, which is using selection criteria and using other methods to be able to select which patients will do well after transplantation, even with immunosuppression.
Liver transplantation for colorectal metastasis was used at the very beginning of the era of liver transplantation, but with very poor outcomes. It was abandoned because of the outcomes. It is exciting to see that after 20 years of not doing it, there was a group in Norway that started again. They are doing liver transplants for colorectal metastases (mets), but with very selected patients.
In Norway, they had a very unusual setting where they had more liver donors than patients on the list waiting for liver transplant. So they can’t share these livers and we’re all jealous, right? Every single country in the West struggles because we don’t have enough livers for the rest of the list. And they had a lot of livers to be able to transplant people.
They decided to transplant some selected patients with colorectal mets that were unresectable. And the surprise was that they found that they were able to get a 60% survival at 5 years. And so that was new. After that, in Norway, they started showing this data to other centers in the world. It wasn’t until this year that we could see not only the long-term data and long-term outcomes of using liver transplantation for unresectable colorectal mets, but also we’re now having data from a prospective clinical trial from France.
It was three countries in the prospective clinical trial: France, Belgium, and Italy. We now see that we have a little stronger data to support the use of liver transplants for unresectable colorectal mets.