Dr. Ryan Merkow, MD, Director of the GI Oncology Regional Therapies Program at the Lurie Cancer Center at Northwestern Medicine talks about a new treatment that is improving cancer patients’ symptoms.
Interview conducted by Ivanhoe Broadcast News in April 2022.
What is an HAI pump?
DR MERKOW: It’s kind of like a meta-port, similar to what patients use normally for chemotherapy, which is usually installed in the chest. A hepatic artery infusion pump is bigger than a meta-port. It’s the size of a hockey puck. And we install it in the abdominal wall. It has a reservoir which holds whatever we’re putting in it – chemotherapy or heparinized saline. A catheter attaches to the pump, which goes into the abdominal cavity, and we surgically place it in one of the arteries – a side branch of the main artery, which goes into the liver. The rationale behind hepatic artery infusion pump treatment is that liver tumors are primarily fed, or they get their blood supply, from the artery, not the portal vein. The liver is unique in that it has two blood supplies. So, we are directly treating the tumors with the chemotherapy by installing it into that hepatic artery.
Is that mainly how you treat liver cancers?
DR MERKOW: It’s complicated. Fortunately, with metastatic colorectal cancer, have lots of tools in our toolbox to treat liver metastases. Some are systemic, like chemotherapy, while there are also local options that are used primarily in the liver. The hepatic artery infusion pump is one of those options. It is unique in that we can deliver very high doses of chemotherapy into the liver at concentrations 300 to 400 times what the liver would normally see compared to systemic chemotherapy. But fortunately, and really the backbone of why this therapy is so unique is that the chemotherapy goes into the liver, but it doesn’t exit the liver – It gets completely metabolized. This allows us to get chemotherapy concentrations so high in the liver in order to really target the disease where it is needed and spare the normal, healthy tissues throughout the rest of the body, from potential side effects.
Is it a lifesaver for these patients?
DR MERKOW: Yes. We believe that it is one tool of many tools, but it’s a very effective and important tool that we use in select situations that can be a game changer for patients.
What happens when the only FDA approved HAI pump is like, “Oh, we’re not going to make it anymore”?
DR MERKOW: We all panicked. Providers as well as patients who either were being worked up for potential placement of these pumps or patients that had pumps already and knew from firsthand experience how important the pump was in their treatment. This was several years ago now, but we came together and made a big fuss about it.. Fortunately, we have a group of very dedicated folks around the country that are very dedicated to this therapy and keeping it going as an important option for our patients.
Do you remember times where you don’t have a pump and you needed a pump?
DR MERKOW: Yes. We went through several lulls where we had no device at all. We couldn’t install pumps. There were a couple six-month periods where we were unable to use this therapy, which is, of course, stressful for everybody, including and most importantly, to the patients who are relying on this therapy to be available when they need it.
When a new pump was FDA approved, was it like a sigh of relief?
DR MERKOW: Yes, it was. We all had a huge sigh of relief. Not only because we have a pump available, but the pump we were using in that interim period, which was a very effective pump that we used in the distant past for this same indication – however, was not FDA approved specifically for hepatic artery infusion pump therapy. So, a lot of us had to jump through extra hoops to make sure we had it available at our hospitals. This newer pump, the Intera pump, is FDA approved.
Is it better and bigger?
DR MERKOW: It’s different. I wouldn’t say it’s better. I would say it’s different. It operates differently.
How does this one work? Does it work the same way as the old pump?
DR MERKOW: It’s a little bit different. It works uniquely through a gas that the pump contains that, when it gets heated through body heat, the chamber within the pump gets pressurized. It delivers the chemotherapy without any battery or any need for energy. It’s based on this gas. It’s unique in that sense. Previously, the pump that we were using in that interim period was battery operated and it had some benefits. There’s a computer within it and we could control it. However, the new pump is what we’re used to. We’ve been putting pumps in for many years, and we know it very well. The majority of the trials that have included hepatic artery infusion pump chemotherapy, used this pump. It’s just a familiar device that we feel most comfortable using.
Can you tell me a little bit about Stephen?
DR MERKOW: It was interesting because we were on the cusp of this pump becoming available. We weren’t totally sure if we were going to have it. A lot of hospitals around the country were interested in acquiring the pump as well. Fortunately, we were one of the first hospitals in the United States that were able to use the new pump. He did wait a little bit, but I was very open with him that we could use the pump we’ve been using for the past several years. But he felt strongly he wanted the newer pump. There were several patients that waited a month or two in order to have the Intera pump.
Does Stephen still have the pump in?
DR MERKOW: Yes, he does. The pump itself, we usually keep it in for at least six months. Most patients, we keep it in for much longer. In some cases, it feels like a security blanket when we’re not using the therapy. For some patients, we’re using therapy longer than six months so, it just depends on the situation. But for him, he does still have it.
How is Stephen doing now?
DR MERKOW: He’s doing excellent.
How long has he had it in?
DR MERKOW: He’s had it in for about eight months or so, and there’s no evidence of recurrence. He’s doing very well. We were able to complete all his therapy and now we’re going to follow along with scans and physical exams.
Does the pump just stay in?
DR MERKOW: The pump just stays in. Although we can take it out at any time. Removing a pump is much more straightforward than putting it in. We don’t remove the catheter, we just remove the pump itself, which is a 20-minute outpatient procedure under local anesthetic and patients do very well.
How is the pump inserted?
DR MERKOW: Depending on the scenario, it can be put in through an open surgery. Usually, we’re putting that pump in at the same time as other things – doing hepatic resections or hepatic ablation, or sometimes combining it with other colorectal surgeries at the same time. So, it all depends on the situation, but we can put it in open, and also put it in with smaller incision using laparoscopic, or robotic surgery
END OF INTERVIEW
This information is intended for additional research purposes only. It is not to be used as a prescription or advice from Ivanhoe Broadcast News, Inc. or any medical professional interviewed. Ivanhoe Broadcast News, Inc. assumes no responsibility for the depth or accuracy of physician statements. Procedures or medicines apply to different people and medical factors; always consult your physician on medical matters.
If you would like more information, please contact:
Megan McCann
(321) 926-5900
Sign up for a free weekly e-mail on Medical Breakthroughs called First to Know by clicking here
