ASCO Education Is Organ Preservation for GEJ and Gastric Cancers Ready for Primetime?
Dr. Pedro Barata and Dr. Ugwuji Maduekwe discuss the evolving treatment landscape in gastroesophageal junction and gastric cancers, including the emergence of organ preservation as a selective therapeutic goal, as well as strategies to mitigate disparities in care. Dr. Maduekwe is the senior author of the article, "Organ Preservation for Gastroesophageal Junction and Gastric Cancers: Ready for Primetime?" in the 2026 ASCO Educational Book.
TRANSCRIPT
Dr. Pedro Barata: Hello, and welcome to By the Book, a podcast series from ASCO that features compelling perspectives from authors and editors of the ASCO Educational Book. I'm Dr. Pedro Barata. I'm a medical oncologist at University Hospitals Seidman Cancer Center and an associate professor of medicine at Case Western Reserve University in Cleveland, Ohio. I'm also the deputy editor of the ASCO Educational Book.
Gastric and gastroesophageal cancers are the fifth most common cancer worldwide and the fourth leading cause of cancer-related mortality. Over the last decade, the treatment landscape has evolved tremendously, and today, organ preservation is emerging as an attainable but still selective therapeutic goal.
Today, I'm delighted to be speaking with Dr. Ugwuji Maduekwe, an associate professor of surgery and the director of regional therapies in the Division of Surgical Oncology at the Medical College of Wisconsin. Dr. Maduekwe is also the last author of a fantastic paper in the 2026 ASCO Educational Book titled "Organ Preservation for Gastroesophageal Junction and Gastric Cancers: Ready for Prime Time?" We explore these questions in our conversations today.
Our full disclosures are available in the transcript of this episode as well.
Welcome. Thank you for joining us today.
Dr. Ugwuji Maduekwe: Thank you, Dr. Barata. I'm really, really glad to be here.
Dr. Pedro Barata: There's been a lot of progress in the treatment of gastric and gastroesophageal cancers. But before we actually dive into some of the key take-home points from your paper, can you just walk us through how systemic therapy has emerged and actually allowed you to start thinking about a curative framework and really informing surgery decision-making?
Dr. Ugwuji Maduekwe: Great, thank you. I'm really excited to be here and I love this topic because, I'm terrified to think of how long ago it was, but I remember in medical school, one of my formative experiences and why I got so interested in oncology was when the very first trials about imatinib were coming through, right? Looking at the effect, I remember so vividly having a lecture as a first-year or second-year medical student, and the professor saying, "This data about this particular kind of cancer is no longer accurate. They don't need bone marrow transplants anymore, they can just take a pill." And that just sounded insane.
And we don't have that yet for GI malignancies. But part of what is the promise of precision oncology has always been to me that framework. That framework we have for people with CML who don't have a bone marrow transplant, they take a pill. For people with GIST. And so when we talk about gastric cancers and gastroesophageal cancers, I think the short answer is that systemic therapy has forced surgeons to rethink what "necessary" really means, right? We have the old age saying, "a chance to cut is a chance to cure." And when I started out, the conversation was simple. We diagnose the cancer, we take it out. Surgery's the default. But what's changed really over the last decade and really over the last five years is that systemic therapy has gotten good enough to do what is probably real curative work before we ever enter the operating room.
So now when you see a patient whose tumor has essentially melted away on restaging, the question has to shift, right? It's no longer just, "Can I take this out?" It's "Has the biology already done the heavy lifting? Have we already given them systemic therapy, and can we prove it safely so that maybe we don't have to do what is a relatively morbid procedure?" And that shift is what has opened the door to organ preservation. Surgery doesn't disappear, but it becomes more discretionary. Necessary for the patients who need it, and within systems that can allow us to make sure that we're giving it to the right patients.
Dr. Pedro Barata: Right, no, that makes total sense. And going back to the outcomes that you get with these systemic therapies, I mean, big efforts to find effective regimens or cocktails of therapies that allow us to go to what we call "complete response," right? Pathologic complete response, or clinical complete response, or even molecular complete response. We're having these conversations across different tumors, hematologic malignancies as well as solid tumors, right? I certainly have those conversations in the GU arena as well.
So, when we think of pathologic CRs for GI malignancies, right? If I were to summarize the data, and please correct me if I'm wrong, because I'm not an expert in this area, the traditional perioperative chemo gives you pCRs, pathologic complete response, in the single digits. But then when you start getting smarter at identifying biologically distinct tumors such as microsatellite instability, for instance, now you start talking about pCRs over 50%. In other words, half of the patients' cancer goes away, it melts down by offering, in this case, immunotherapy as a backbone of that neoadjuvant. But first of all, this shift, right, from going from these traditional, "not smart" chemotherapy approaches to kind of biologically-driven approaches, and how important is pCR in the context of "Do I really need surgery afterwards?"
Dr. Ugwuji Maduekwe: That's really the crux of the entire conversation, right? We can't proceed and we wouldn't be able to have the conversation about whether organ preservation is even plausible if we hadn't been seeing these rates of pathologic complete response. If there's no viable tumor left at resection, did surgery add something? Are we sure?
The challenge before this was how frequently that happened. And then the next one is, as you've already raised, "Can we figure that out without operating?" In the traditional perioperative chemo era, pathologic complete response was relatively rare, like maybe one in twenty patients. When we go to more modern regimens like FLOT, it got closer to one in six. When you add immunotherapy in recent trials like MATTERHORN, it's nearly triple that rate.
And it's worth noting here, I'm a health services-health disparities researcher, so we'll just pause here and note that those all sound great, but these landmark trials have significant representation gaps that limit and should inform how confidently we generalize these findings.
But back to what you just said, right, the real inflection point is MSI-high disease where, with neoadjuvant dual-checkpoint blockade, trials like NEONIPIGAS and INFINITY show pCR rates that are approaching 50% to 60%. That's not incremental progress, that's a whole new different biological reality.
What does that mean? If we're saying that 50% to 60% of the people we take to the OR at the time of surgery will end up having no viable tumor, man, did we need to do a really big surgery? But the problem right now is the gold standard, I think we would mostly agree, the gold standard is pathologic complete response, and we only know that after surgery.
I currently tell my patients, right, because I don't want them to be like, "Wait, we did this whole thing." I'm like, "We're going to do this surgery, and my hope is that we're going to do the surgery and there will be no cancer left in your stomach after we take out your stomach." And they're like, "But we took out my stomach and you're saying it's a good thing that there's no cancer."
And yes, right now that is true because it's a measure of the efficacy of their systemic therapy. It's a measure of the biology of the disease. But should we be acting on this non-operatively? To do that, we have to find a surrogate. And the surrogate that we have to figure out is complete clinical response. And that's where we have issues with the stomach.
In esophageal cancer, the preSANO protocol, which we'll talk about a little bit, validated a structured clinical response evaluation. People got really high-quality endoscopies with bite-on biopsies. They got endoscopic ultrasounds. They got fine-needle aspirations and PET-CT, and adding all of those things together, the miss rate for substantial residual disease was about 10% to 15%. That's a number we can work with.
In the stomach, it's a lot more difficult anatomically just given the shape of people's stomachs. There's fibrosis, there's ulceration. A fair number of stomach and GEJ cancers have diffuse histology which makes it difficult to localize and they also have submucosal spread. Those all conceal residual disease.
I had a recent case where I scoped the patient during the case, and this person had had a 4 cm ulcer prior to surgery, and I scoped and there was nothing visible. And I was elated. And on the final pathology they had a 7 cm tumor still in place. It was just all submucosal. That's the problem. I'm not a gastroenterologist, but I would have said this was a great clinical response, but because it's gastric, there was a fair amount of submucosal disease that was still there.
And our imaging loses accuracy after treatment. So the gap between what looks clean clinically and what's actually there pathologically remains very wide. So I think that's why we're trying to figure it out and make it cleaner. And outside of biomarker-selected settings like MSI-high disease, in general, I'm going to skip to the end and our upshot for the paper, which is that organ preservation, I would say for gastric cancer particularly, should remain investigational. I think we're at the point where the biology is increasingly favorable, but our means of measurement is not there yet.
Dr. Pedro Barata: Gotcha. So, this is a perfect segue because you did mention the SANO, just to spell it out, "Surgery As Needed for Oesophageal" trial, so SANO, perfect, I love the abbreviation. It's really catchy. It's fantastic, it's actually a well-put-together perspective effort or program applying to patients. And can you tell us how was that put together and how does that work out for patients?
Dr. Ugwuji Maduekwe: Yeah, I think for those of us in the GI space, we have SANO and then we also have the OPRA for rectum. SANO for the upper GI is what takes organ preservation from theory to something that's clinically credible.
The trial asked a very simple question. If a patient with a GEJ adenocarcinoma or esophageal adenocarcinoma achieved what was felt to be a clinical complete response after chemoradiation, would they actually benefit from immediate surgery? And the question was, "Can you safely observe?" And the answer was 'yes'. You could safely observe, but only if you do it right. And what does that mean? At two years, survival with active surveillance was not inferior to those who received an immediate esophagectomy. And those patients had a better early quality of life. Makes sense, right? Your quality of life with an esophagectomy versus not is going to be different.
That matters a lot when you consider what the long-term metabolic and functional consequences of an esophagectomy are. The weight loss, nutritional deficiencies that can persist for years. But SANO worked because it was very, very disciplined and not permissive. You mentioned rigor. They were very elegant in their approach and there was a fair amount of rigor.
So there were two main principles. The first was that surveillance was front-loaded and intentional. So they had endoscopies with biopsies and imaging every three to four months in the first year and then they progressively spaced it out with explicit criteria for what constituted failure. And then salvage surgery was pre-planned. So, the return-to-surgery pathway was already rehearsed ahead of time. If disease reappeared, take the patient to the OR within weeks. Not sit, figure out what that means, think about it a little bit and debate next steps. They were very clear about what the plan was going to be.
So they've given us this blueprint for, like, watching people safely. I think what's remarkable is that if you don't do that, if you don't have that infrastructure, then organ preservation isn't really careful. It's really hopeful. And that's what I really liked about the SANO trial, aside from, I agree, the name is pretty cool.
Dr. Pedro Barata: Yeah, no, that's a fantastic point. And that description is spot on. I am thinking as we go through this, where can this be adopted, right? Because, not surprisingly, patients are telling you they're doing a lot better, right, when you don't get the esophagus out or the stomach out. I mean, that makes total sense.
So the question is, you know, how do you see those issues related to the logistics, right? Getting the multi-disciplinary team, getting the different assessments of CR. I guess PETs, a lot of people are getting access to imaging these days. How close do you think this is, this kind of program, to be implemented? And maybe I would assume it might need to be validated in different settings, right, including the community. How close or how far do you think you see that being applied out there versus continuing to be a niche program, watch and wait program, in dedicated academic centers?
Dr. Ugwuji Maduekwe: I love this question. So I said at the top of this, I'm a health equity/health disparities researcher, and this is where I worry the most. I love the science of this. I'm really excited about the science. I'm very optimistic. I don't think this is a question of "if," I think it's a question of "when." We are going to get to a point where these conversations will be very, very reasonable and will be options.
One of the things I worry about is: who is it going to be an option for? Organ preservation is not just a treatment choice, and I think what you're pointing out very rightly is it's a systems-level intervention. Look at what we just said for SANO. Someone needs to be able to do advanced endoscopy, get the patients back. We have to have the time and space to come back every three to four months. We have to do molecular testing. There needs to be multi-disciplinary review. There needs to be intensive surveillance, and you need to have rapid access to salvage surgery.
Where is that infrastructure? In this country, it's mostly in academic centers. I think about the panel we had at ASCO GI, which was fantastic. And as we were having the conversation, you know, we set it up as a debate. So folks were debating either pro-surveillance or pro-surgery. But both groups, both people, were presenting outcomes based on their centers. And it was folks who were fantastic. Dr. Molena, for example, from Memorial Sloan Kettering was talking about their outcomes in esophagectomies [during our session at GI26], but they do hundreds of these cases there per year.
What's the reality in this country? 70% to 80% to 90%, depending on which data you look at, of the gastrectomies in the United States occur at low-volume hospitals. Most of the patients at those hospitals are disproportionately uninsured or on government insurance, have lower income and from racial and ethnic minority groups.
So if we diffuse organ preservations without the system to support it, we're going to create a two-tiered system of care where whether you have the ability to preserve your organs, to preserve bodily integrity, depends on where you live and where you're treated.
The other piece of this is the biomarker testing gap. One of the things that, as you pointed out at the beginning, that's really exciting is for MSI-high tumors. Those are the patients that are most likely to benefit from immunotherapy-based organ preservation. But here's the problem. If the patient isn't tested at time of initial diagnosis before they ever see me as a surgeon, the door to organ preservation is closed before it's ever open. And testing access remains very inconsistent across academic networks.
And then there's the financial toxicity piece where, for gastrectomy, pancreatectomy, I do peritoneal malignancies, more than half of those patients experience significant financial toxicity related to their cancer treatment. We're now proposing adding at least two years, that's the preliminary information, right? It's probably going to be longer. At least a couple of years of surveillance visits, repeated endoscopies, immunotherapy costs. How are we going to support patients through that? We're going to have to think about setting up navigation support, geographic solutions, what financial counseling looks like. My patient for clinic yesterday was driving to see me, and they were talking about how they were sliding because it was snowing. And they were sliding for the entire three-hour drive down here.
Are we going to tell people like that that they need to drive down to, right, I work at a high-volume center, they're going to need to come here every three months, come rain or snow, to get scoped as opposed to the one-time having a surgery and not needing to have the scopes as frequently? My concern, like I said, I'm an optimist, I think it is going to work. I think we're going to figure out how to make it work. I'm worried about whether when we deploy it, we widen the already existing disparities.
Dr. Pedro Barata: Gotcha, and that's a fantastic summary. And as I'm thinking also of what we've been talking in other solid tumors, which one of the following do you think is going to evolve first? So we are starting to use more MRD-based assays, which are based on blood test, whether it's a tumor-informed ctDNA or non-informed. We are also trying to get around or trying to get more information response to systemic therapies out of RNA-seq through gene expression signatures, or development of novel therapeutics which also can help you there. Which one of these areas you think you're going to help this SANO-like approach move forward, or you actually think it's actually all of the above, which makes it even more complicated perhaps?
Dr. Ugwuji Maduekwe: I think it's going to be all of the above for a couple of reasons. I would say if I had to pick just one right now, I think ctDNA is probably the most promising and potentially the missing piece that can help us close the gap between clinical and pathologic response.
If you achieve clinical complete response and your ctDNA is negative, so you have clinical and molecular evidence of clearance, maybe that's a low-risk patient for surveillance. If you have clinical complete response but your ctDNA remains positive, I would say you have occult molecular disease and we probably need intensified therapy, closer monitoring, not observation. I think the INFINITY trial is already incorporating ctDNA into its algorithm, so we'll know. I don't think we're at the point where it alone can drive surgical decisions. I think it's going to be a good complement to clinical response evaluation, not a replacement.
The issue of where I think it's probably going to be multi-dimensional is the evidence base: who are we testing? Like, what is the diversity, what is the ancestral diversity of these databases that we're using for all of these tests? How do we know that ctDNA levels and RNA-seq expression arrays are the same across different ancestral groups, across different disease types?
So I think it's probably going to be an amalgam and we're going to have to figure out some sort of algorithm to help us define it based on the patient characteristics. Like, I think it's probably different, some of this stuff is going to be a little bit different depending on where in the stomach the cancer is. And it's going to be a little bit more difficult to figure out if you have a complete clinical response in the antrum and closer to the pylorus, for example. That might be a little bit more difficult. So maybe the threshold for defining what a clinical complete response needs to be is higher because the therapeutic approach there is not quite as onerous as for something at the GE-junction.
Dr. Pedro Barata: Wonderful. And I'm sure AI, whether it's digitization of the pathology from the biopsies and putting all this together, probably might play a role as well in the future.
Dr. Maduekwe, it's been fantastic. Thank you so much for sharing your insights with us and also congrats again for the really well-done review published.
For our listeners, thank you for staying with us. Thank you for your time. We will post a link to this fantastic article we discussed today in the transcript of this episode. And of course, please join us again next month on the By the Book Podcast for more insights on key advances and innovations that are shaping modern oncology. Thank you, everyone.
Dr. Ugwuji Maduekwe: Thank you. Thank you for having me.
Watch the ASCO GI26 session: Organ Preservation for Gastroesophageal and Gastric Cancers: Ready for Primetime?
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Disclosures:
Dr. Pedro Barata:
Stock and Other Ownership Interests: Luminate Medical
Honoraria: UroToday
Consulting or Advisory Role: Bayer, BMS, Pfizer, EMD Serono, Eisai, Caris Life Sciences, AstraZeneca, Exelixis, AVEO, Merck, Ipson, Astellas Medivation, Novartis, Dendreon
Speakers' Bureau: AstraZeneca, Merck, Caris Life Sciences, Bayer, Pfizer/Astellas
Research Funding (Inst.): Exelixis, Blue Earth, AVEO, Pfizer, Merck
Dr. Ugwuji Maduekwe:
Leadership: Medica Health
Research Funding: Cigna