New Treatments for Liver Metastases Improve Survival, Outcomes Across Age Groups: Yuman Fong, MD

Colorectal cancer, once mostly affecting older adults, is now being seen in younger people as well, says Yuman Fong, MD, cancer surgeon, City of Hope. Major advances in surgical and ablative treatments for colorectal liver metastases (CRLM) have greatly improved patient survival, offering a cure or significant life extension for many who previously had little hope.

Fong presented on this topic during a session titled “Liver-Directed Approaches and Transplantation for Unresectable Colorectal Liver Metastasis” at this year’s American Society of Clinical Oncology (ASCO) Gastrointestinal (GI) Cancers Symposium.

This transcript was lightly edited for clarity; captions were auto-generated.

Transcript

Can you share data on the prevalence of CRLM in the US, and how does this prevalence shape the urgency for improving detection and treatment?

Colorectal cancers happen in about 150,000 people in this country every year. It is the fourth most common cancer, and so it's certainly an important cancer to deal with. Half the people who have colon cancer will eventually end up with liver metastases, simply because the tumor cells that are draining out of the tumors come up the portal vein, and the first blood vessel it goes to goes straight to the liver. The other interesting thing that's been happening is that it's been very clear that over the years, there's a younger and younger population that is getting this cancer. [It] used to only be seen in people after age 50. Now there's a second group of individuals that peak around age 39 or 40 that seem to get this cancer, and in that group, it's the second highest rate of killing them from cancer of any cancer. So again, [it’s] very interesting how there's a change in epidemiology over the last years.

What key factors guide the choice between surgical or ablative treatment for CRLM in clinical practice?

Let me just frame for you what we do for colorectal liver metastases. Until the 1980s we actually didn't do very much about it. We used to think if tumor cells had gotten into the blood and gotten to the liver, [they] must be everywhere, and it turned out we were wrong. We discovered we were wrong because in the 1980s, CT scans were invented. We were now able to look inside a human being without opening them up. And suddenly we noticed that as the tumors got bigger and bigger in the liver, many times they were never found anywhere else. Surgeons like me started removing the tumors from the liver, starting in the late 1980s. What we have discovered is that if we can clear the liver, about 40% of the people are cured. They actually go on to old age, and that was a huge discovery, and that's what drives therapy now.

If it is possible to clear the liver, that's what we do, because it again cures patients about 40% of the time. And for the patients that we don't cure, we certainly extend their lives by years. This is not like extending it by 6 weeks or 6 months. This is probably extending their lives by at least 3 or 4 years, even if we don't cure them.

Then in the 1990s we came up with a whole set of treatments called ablative treatments that destroy tumors by heat or by freezing or by injecting different chemicals, and the best of those has turned out to be microwave ablation; by putting a needle in the tumor in a period of between 3 and 10 minutes, we can kill the tumor completely, if it’s small enough. And so for tumors that are very, very small, I now don't really even need to operate on them if they are centrally located in the liver, meaning that away from the surfaces, we can ask an intervention radiologist to go and burn them to death, and so it really has changed how we think of small tumors. Bigger tumors, in general, we still have to remove them.

Lastly, the other evolution that's happened in the last year that’s changed how we think about things [is that] if it's tumors that are very near the edges of the liver, now we could reach in with a robot, making incisions that are sometimes less than 8 millimeters, and then within the hour clear the tumors and get the patients out of the hospital within 24 to 48 hours. So last year, we published the paper where we looked at our first 308 patients that we did outpatient liver surgery on, and they and the results are quite remarkable: 2% complication, 1.6% readmission, and so that has additionally changed the equation. And so for smaller tumors, we can now do it by minimally invasive surgery. For small central tumors, we do it by ablation. But the bottom line is, we want to physically clear the liver, if it's possible. We’re now also able to resect some of the tumors, the bigger ones, and burn the other tumors in the operating room so that we combine the two to save as much functional liver as possible.

The world of how we deal with the liver tumors from colon cancer has really changed, but the good news is that it really has improved the outcomes of patients. When I see someone with metastatic colon cancer in the office now, there's at least a 60% chance I will know them 5 years later, which is quite remarkable, because when I graduated from medical school in 1984, everybody died from the disease if they had it.