Webinar | Understanding ctDNA: A New Tool for Bladder Cancer Care

August 4, 2025

In this easy-to-understand webinar, Dr. Joaquín Bellmunt from Dana-Farber Cancer Institute will explain how ctDNA works and how it can help people with muscle-invasive or advanced bladder cancer. He will talk about how this test might help choose the best treatment, especially after surgery or chemotherapy, and how it gives patients more peace of mind.

Year: 2025

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Full Transcript of Understanding ctDNA: A New Tool for Bladder Cancer Care

Stephanie Chisolm:

So today’s topic, as I mentioned, is understanding ctDNA. It’s a new tool for bladder cancer care and why is it so important? You know it’s a simple blood test that looks for traces of DNA in your bloodstream and now we’re going to hear about why it’s becoming really important for patients with bladder cancer. Dr. Bellmunt has been a friend of BCAN for many, many years. And I don’t know that this was even on your radar 20 years ago when BCAN got started, was it, Dr. Bellmunt?

Dr. Joaquim Bellmunt:

Yeah, no, no, absolutely. We’re discussing, I joined the first meetings of BCAN long ago when, when we didn’t have any white hair yet. So here we are.

Stephanie Chisolm:

Right. Yeah, which is just amazing. So much has happened in the last 20 years. So, this just can help detect cancer earlier, it can show whether your cancer treatment is working, maybe even spot signs of recurrence. For patients with muscle invasive or advanced bladder cancer knowing your ctDNA can really help to help them decide on more and specific treatments options for them and more personalized treatment, and maybe a greater peace of mind because you know you’re doing everything you need to do for your particular tumor type. So we are really delighted to have Dr. Joaquim Bellmunt here. He’s an associate professor at Harvard Medical School and director of the Bladder Cancer Center at the Dana-Farber Cancer Institute in Boston. Dr. Bellmunt will explain how ctDNA works and why staying informed about this new tool can really make a difference in your care. Professor Bellmunt is also a senior researcher at the Instituto Hospital del Mar de Investigaciones. I’m not going to say this, can you say it, Dr. Bellmunt?

Dr. Joaquim Bellmunt:

So this is from Yeah, I still have my lab, all lab in Barcelona at IMIM Hospital del Mar, yeah.

Stephanie Chisolm:

Great. So you really do pop back and forth and are very engaged in global bladder cancer care. As a genitourinary medical oncologist, you practice as a principal investigator in so many clinical trials and we really appreciate your time and sharing your expertise. I’m going to turn the screen over to you. If you want to share your slides now, you’re welcome to do that.

Dr. Joaquim Bellmunt:

Yeah.

Stephanie Chisolm:

And I’m going to turn off my camera and I’ll be in the background and we’ll get to questions and answers at the end of today’s program.

Dr. Joaquim Bellmunt:

All right, excellent. Thanks Stephanie for the kind introduction and as mentioned, it’s a pleasure to be here on these 20 years of impact of BCAN. As mentioned, I, I joined the first the first think tank meetings like almost yeah 15, 17 years ago and I have been involved in collaborating, so that’s a great, great effort and I want to thank Stephanie, Allison, Patricia for making this lecture to happen despite I cancel because of some unexpected commitments.

So yeah so I’m going to explain you a bit what’s the present status of the ctDNA as a new tool for bladder cancer care.

Dr. Joaquim Bellmunt:

So, some of some of the things that I’m going to explain that are listed here, likely some are not fully accomplished, so but we are trying just to learn a bit what ctDNA is and how it can help find cancer. That’s one aim. Also, how it can help doctors choose or change treatment. Still we are not there, but we are getting there. How it may show if cancer comes back before even the scans can show that, and how it helps patient feel more in control of their care. So those are the main aims. As mentioned, we are heading there. So we still are not fully accomplished all these aims.

Dr. Joaquim Bellmunt:

So first I’m going to introduce several terms just to make clear what we’re talking about. So the first term is the liquid biopsy. Liquid biopsy is a biopsy, but instead of getting tissue, we are getting blood and we are trying to analyze the blood if there are cells there. So on the first documented evidence of a solid tumor material in peripheral blood is coming from this paper that is 1869 in Australia where this was a patient that died and then in the blood they were able to capture cancer cells. So this has the first documented like paper or, or, or experiments just showing that the tumor is like spreading and circulating in the blood.

Dr. Joaquim Bellmunt:

And then going back again to the term liquid biopsy. Liquid biopsy is a wide term. And in the liquid biopsy, meaning doing a biopsy in the blood, we can find different components. And you can see here in this cartoon in the right side you can look for ctDNA or cell-free DNA, and we will talk about what’s the difference between cell-free, it’s cfDNA, or ctDNA. That’s very important is that I have underlined the T and the F. But you, you can look for circulating tumor cells, you can look for extra vesicles, proteins. So so many things under the concept of liquid biopsy. So what we’re going to talk about is the cell-free DNA in the blood plasma and this is a very easy to obtain like a research and there we can capture the cell-free DNA and the cell tumor DNA, the ctDNA.

So three concepts here, cell-free DNA, circulating tumor DNA, and this is completely distinct from the what we have heard on circulating tumor DNAs. And I, I could say that cell-free DNA is like whatever DNA is floating around is named cfDNA and the one that is tumor specific, and we have tools to identify that these DNA, because of mutations and copy numbers is a tumor DNA, and then we have these CTCs.

Dr. Joaquim Bellmunt:

So we are going to focus on the concept of cell-free DNA. Cell-free DNA, that’s the first thing meaning is DNA that is found in the blood and this mainly coming when the cells die, like they are going through like what we call apoptosis. The DNA inside the cells are shed into the blood. And we know that the the normal cells die too. So when the majority of the cell-free DNA that is found in the blood is coming from normal hematologic precursors, and usually we see fragments of a 167 base pair.

Dr. Joaquim Bellmunt:

So very, very, very tiny fragments. And the amount of DNA that is found, of cell-free DNA that is found in the blood is between 5, 10 nanograms per mL of plasma, meaning that is very, very tiny amounts that we are now having technologies that are able to capture this DNA that is floating, isolated this specific CT, circulating tumor, DNA and obtain results and provide guidance.

Dr. Joaquim Bellmunt:

So another thing is that there are the ctDNA, circulating tumor DNA, there are different tests and now are commercially available. And obviously we all the time that we’re talking about ctDNA, the first thing that we need to ask is which tests are you going to use to monitor my ctDNA? And there are tests that are mainly focusing on detecting tumor, detecting cancer, but there are other ones that are in fact going not further, in a different way. They are characterizing which type of cancer cells are there.

So this is completely two different concepts. And obviously the techniques are improving and we know all the companies that are investigating on that, they are increasing on sensitivity and specificity, but as still of now still we are a bit suboptimal. So those are not 100% sensitive and not 100% specific. There are new evolving techniques that I’m not going like to present at the epigenomic techniques that are emerging trying to like better characterize the cell ctDNA floating in our, our, our blood.

Dr. Joaquim Bellmunt:

So three, three, main groups of areas on how the CT, the circulating tumor, DNA test might help managing cancer. The first is that we can improve cancer screening. And we know this paper in the right in patients that these predisposing cancer syndrome Li-Fraumeni. Cell-free DNA was used to identify early appearance of cancer. And also we are presently using for a concept that is named minimal residual disease. And minimal residual disease is a concept coming from hematological malignancies, leukemias that there were tests that we were able to detect like very tiny amounts of translocations for example in chronic myeloid leukemia. So this is also now being done in a, in a, solid tumors like bladder cancer. That’s the first group.

Dr. Joaquim Bellmunt:

The second group, we can use ctDNA as a way to monitor the response to therapy. As you can see in the paper in the right, plasma ctDNA as a treatment response biomarker in metastatic cancers, a correlation with the resist criteria, the classical radiological criteria, and also we can estimate how aggressive is a cancer, a tumor. So in the right you can see here this paper for Nature Communications 2021 in unselected first-line metastatic urothelial cancers, patient having low ctDNA, all these patients were doing much better than patients having high ctDNA.

Dr. Joaquim Bellmunt:

The third group of concepts where we can use the ctDNA is predicting treatment efficacy, also identifying resistant mechanisms. And now this is being used for example in tumors like lung cancer that we have drugs that are under treatment, the tumors change their phase and they a create new mutations. And through monitoring the blood we are able to say, “This treatment is no longer responding.” Then we capture the changes that the tumor has developed and then we implement a new therapy for this resistance. So we can characterize the biology and the evolution.

So a lot of areas where CTNA is helping on making decisions, assessing the, the prognosis, and establishing the best treatment for patients.

Dr. Joaquim Bellmunt:

As mentioned, the CTNA test is not that one size fits all and we mentioned that. So there are tests that are going to help us to detect cancer and it’s not going to provide in general any additional information, say, well,  “You have malignant cells in your blood.” Or there are others that are like characterizing more specifically the type of mutations or the type of genomic alterations that this tumor is having.

Dr. Joaquim Bellmunt:

So focusing on detecting and detecting is a way to say well, I want to make sure that this, this, tumor is in complete remission and you want to make sure that there is no minimal residual disease. For that, there are two different type of, of platforms. One is what is called a tumor-informed. This is a customized, customized, is a bespoke platform where the we create a personal… We create, the company who’s doing that is creating a personal test to follow this patient. That’s an example of the Natera Signatera platform. So this is specific test. Obviously you need to, and we’re going to discuss more about this platform that is widely used in bladder cancer.

And then there are different platforms that are tumor-naive, so meaning those are not platforms that are personalized. So this is like we know that in bladder cancer there are specific genomic alterations that are well-known based on the TCGA work and so on. And we create platforms to look for specific mutations or genomic alterations that we know are highly prevalent in bladder cancer. And this is using the same test for all the patients. It’s not, that’s different that tumor-naive to the tumor-informed where we are using a very highly personalized approach to monitor the minimal residual disease. Now, as mentioned, minimal residual disease, very important we’re going to discuss its role for example in the, in the, follow-up after surgery in patients with muscle-invasive bladder cancer.

Dr. Joaquim Bellmunt:

So, let’s let’s go back a bit. When several emerging studies, these show the benefit of using the ctDNA. So you can see here ctDNA detection after surgery indicating the what we call the molecular, this is progression. And this is seen before you see a clinical relapse meaning until the radiographic images are coming positive. And these are publications from 2017, 2018. We can see here that in lung patients that the ctDNA was negative, no no cells found after surgery, the relapse-free survival was higher than patients having ctDNA positives meaning DNA material from the tumor floating in the blood. The same for bladder, the same for colorectal cancer. So this is not only applicable to bladder, but as you can see to so many different tumor types.

Dr. Joaquim Bellmunt:

Also we mentioned that before, and this coming from a phase two study of Pembrolizumab in advanced solid tumors, it was shown that low baseline ctDNA levels are associated with better survival and progression free survival is a way to monitor the tumor burden. So if you have less cells in your blood, your outcome is going to be much better.

Dr. Joaquim Bellmunt:

And obviously if this is like a, like a decrease by the treatment, and this is something that we see in here, this is the same study in these initial studies. As mentioned this was published in 2020. We can see that patients receiving Pembrolizumab. If there was a reduction of the amount of circulating tumor DNA in the blood, those patients were doing much better. So it’s a way to predict monitor if the patient is responding well or not responding well under treatment. In this case it’s for immunotherapy.

Dr. Joaquim Bellmunt:

So let’s focus on the area where the ctDNA has been expanded and we have done a lot of work on the that. That is the muscle-invasive bladder cancer. Just to refresh your memory, muscle invasive is when the tumor is invading the muscle of the bladder, it requires neoadjuvant chemotherapy or neoadjuvant chemotherapy nowadays, followed by surgery. You need to remove the bladder or sometimes we can use radiation therapy. And then after that, patients need to receive complementary adjuvant treatment after the surgery. So that’s the setting of muscle invasive.

And the use of ctDNA has shown to be a prognostic biomarker and it helps us to understand the dynamics of how the treatment evolves and then obviously can be used, as, as Stephanie was mentioning, to guide treatment to improve, survival quality of life, or maybe to select patients that don’t need to receive additional therapy. So this is a still not definitive, but we are working on trials just to make sure that all these endpoints and are fully established in the management of muscle-invasive bladder cancer.

Dr. Joaquim Bellmunt:

So here is the first paper and now I’m going to focus my attention on bladder cancer specifically. So this is the first paper that did show that using ctDNA, and this was using this Natera Signatera platform, is helpful to predict response to neoadjuvant   chemotherapy, outcomes after surgery, and then monitoring the patients after the resection of the, of the, of the bladder tumor. So you can see here is that in this perspective follow up of patients, so authors and this is from Denmark, they did collect plasma before the patients are starting receiving neoadjuvant chemotherapy. Some plasma samples were collected in during the treatment when they were receiving neoadjuvant chemotherapy. Patient had surgery here and then these patients were followed with a plasma collection.

And just to clarify, the plasma, so if you centrifuge the blood, you are going to find the red blood cells in the bottom, you are going to find the white blood cells in the middle. And then the plasma is what is the the supernatant, and this is where we can extract the, the, ctDNA. So this is what you see here in these tubes like there, there are two different, two different, sorry, two different, two different layers. So yeah, so this report, this is a JCO, 2019, so the this was with chemotherapy.

Dr. Joaquim Bellmunt:

And what this trial did show, they demonstrated that if you have ctDNA positive at baseline, the likelihood of have recurrent disease was higher, 43% versus 3% in patients being negative. While the patients were receiving neoadjuvant chemotherapy, if the ctDNA was positive, 75% of patients did recur despite receiving neoadjuvant chemotherapy.

And the same for surveillance. So if the, if the, ctDNA was positive, and this was seen in 27% of patients, the, the, likelihood of recurrence having positive ctDNA was 76% versus 0% in patients having ctDNA negative. So no, no, no minimal residual disease found in the blood, no circulating tumor DNA. So as mentioned, this is the first like report published in Journal of Clinical Oncology in 2019 telling us that the ctDNA is a useful tool just to predict what’s going to happen in terms of outcome.

Dr. Joaquim Bellmunt:

And just to say, well, what’s happening, what’s the timeframe where you see a ctDNA positive before you see clinically evident disease in the, in the scans? So in this study, in this cohort, it was so four months before the CT scans or the MRIs became positive, ctDNA were positive before and having normal imaging. So the ctDNA positivity predates or predicts what’s trying to be seen in radiographs or in imaging at least at the median time of four months or 123 days.

So with that still is not yet there. Maybe early implementation of therapy or likely this might might mean a lot in terms of improving subsequent survival or, ortherapeutic benefits. We are now exploring all these areas. Still having a ctDNA positive doesn’t mean, oh yeah, you need to change therapy. Maybe in the adjuvant setting we’re going to discuss that maybe it’s applicable there and we have trials ongoing. But in general in other settings, you all the time want to get like proven evidence of the disease is there. And now we are using PET/CTs that are much more sensitive, meaning that this timeframe in between positivity for ctDNA and positivity for imaging is going to be shortened.

Dr. Joaquim Bellmunt:

So moving specifically for how the ctDNA in immunotherapy through the patients in this muscle invasive came up. So here you have this, this manuscript. This was published in Lancet Oncology. And now you know that there are two drugs that are approved for treatment of muscle-invasive bladder cancer, high risk muscle-invasive bladder cancer after surgery, meaning in the adjuvant setting. We have Nivolumab FDA-approved based on disease-free survival benefit. Also, Pembrolizumab.

There were, and those was based on these two trials that came back positives, the AMBASSADOR and the Checkmate 274. And there was a third trial that people has forgotten. It was lead by myself. But this trial using Atezolizumab in the same setting, meaning in the adjuvant setting versus placebo. This trial was negative. So yeah, there might be reasons, maybe it’s not the drug itself that is not working.

Dr. Joaquim Bellmunt:

And here you can see the design of this trial. So patients with muscle invasive after having received neoadjuvant chemotherapy having had surgery, if there, there was a still disease, they were randomized at that time to receive immunotherapy versus observation because there was no standard at this time point.

So still these three trials were running together, and the main point was disease-free survival as you can see here.

Dr. Joaquim Bellmunt:

And as mentioned unfortunately there was no benefit although there was some initial benefit in here patients receiving Atezolizumab, but in the end this was not statistically significant. So this trial was negative. But all the times when we have a trial that is negative, we, you can do a deep dive and try to find if there is something that we can obtain from this trial?

So from this trial we prospectively collect plasma samples…

Dr. Joaquim Bellmunt:

Before starting treatment with adjuvant Atezolizumab and during treatment. And we were in retrospect with… Tom Powles was the lead on IMvigor. We start to analyze the ctDNA in those patients receiving Atezolizumab and also in the patients that didn’t receive Atezolizumab in the, in the observation arm. So here’s a summary of how this, this, platform is working. So this is a personalized platform, it’s a bespoke assay. So these need to be done specifically for each one of the tumors for each one of the patients.

And the way that it’s working is that in the very beginning we get the tumor from the cystectomy and we sequence the tumor and also we sequence the matched normal. And what we do is we merge this data in order to identify which mutations are completely different and not found in the normal tissue, in the germline tissue. And with that, a 16 tumor-specific mutation platform is made. So you need to do next-generation sequencing in the very beginning, sequencing the tumor, sequencing the normal. Likely this is much, much, much expensive, right.

But then once you have identified these 16 tumor-specific mutations, you design a personalized multiplex PCR assay that is being used sequentially to check the system mutations in the peripheral blood of the patient. So this is much more cheaper, it’s simple, and with that you can follow the, the, ctDNA. And this ctDNA we are not going to know which specific mutations that the patient have, the aim here is to detect if there is minimal residual disease. And in the very beginning when this trial was designed, we considered ctDNA positive is if more than two of these 16 mutations that are tumor-specific, patient-specific were detected. Nowadays, there are different ways to measure. There is a more quantitative way. This platform now is being optimized just to look for more than 16, and also we can characterize the type of mutation. But this is the way that the initial Natera Signatera platform was used for this trial and also for the other one, the neoadjuvant chemotherapy trial.

Dr. Joaquim Bellmunt:

So, so what we found when we analyzed the samples of these patients that were randomized to receive immunotherapy versus observation, we saw that in this IMvigor010 trial we confirmed the prognostic value of ctDNA. So you can see here the two slopes here, those are the patients with ctDNA negative, they do much better whatever the treatment they receive. You can see here that the blue is atezolizumab, the red is observation. So here these patients having ctDNA negative, they do much better than the patients that had overall ctDNA positivity as shown here.

So confirming the value prognostic, the prognostic value of ctDNA in this setting. But the most interesting thing, and as mentioned the IMvigor010 was a negative trial, but when focusing our attention here in these patients being ctDNA positive, we saw that patients that receive Atezolizumab, that is the blue line, did much better. And you can see here with the p-value statistically significant compared to the patients that were on observation suggesting that maybe, maybe immunotherapy was really helpful in patients being ctDNA positive. And this was seen for disease-free survival and the same for overall survival.

So this data was finally published in Nature, one of the highly prestigious journals and because it was a change on the paradigm, but obviously this was retrospective, this was in this IMvigor010 trial and we were willing to confirm that this was real in a prospective trial.

Dr. Joaquim Bellmunt:

And this is why we designed the subsequent trial, the IMvigor011. So the IMvigor011 was trying to test if in patients being ctDNA positive, randomized… And as mentioned this patient is the same, patient receive chemotherapy, surgical removal of the tumor, there is nothing on imaging so they are considered to be like free of disease, and then you check the blood and say, “Well, this patient that is free of disease after surgery, the ctDNA is positive,” and these patients when the ctDNA was positive were randomized 2:1 to receive Atezolizumab or placebo.

This trial obviously now would not be ethically ethical because we have standard of care here, but at that time that when the trial was designed, so there was, this was the only way to demonstrate that ctDNA positive patients were benefiting from Atezolizumab. This trial completely accrual. We’re going to see the results of this that is the main part of the trial in the next coming meeting this year. So this is going to be very nice to see if the ctDNA is identifying patients that benefit from receiving immunotherapy versus placebo.

But obviously in this trial we need to screen patients for ctDNA. And then obviously there were. There were a cohort of patients that the ctDNA was negative and we decided just to follow these patients followed for with radiographic imaging as a standard of care and surveillance without no treatment. So this group is what we define as ctDNA negative patients, meaning patients that after surgery there is no evidence of ctDNA positivity in the blood. So those patients are patients that are disease-free, negative ctDNA. And we monitor these patients. We have been monitoring, as mentioned. This is in a clinical trial. The trial is focusing on here, but those are the patients not included in the trial. And we have We did monitor these patients for more than a year.

Dr. Joaquim Bellmunt:

And the results, those were presented at AUA. I present this data at the SUO last year.

Dr. Joaquim Bellmunt:

So let’s summarize the findings. We are talking on these patients that are high-risk patients that the surgery has gone well, everything is being removed, imaging is negative, but and they have the ctDNA is negative. So we identify 171 patients meeting this criteria having follow-up for at least one year monitoring every six, eight weeks ctDNA. So continuously being negative, negative, negative, negative. It’s not a single time point that is the one that we obtain in the IMvigor010.

Dr. Joaquim Bellmunt:

So what we can see here in this population of patients with negative ctDNA, the disease free survival is at a year and a half 88%, meaning still there are patients that recur. This is what I’m saying that this test is not 100% sensitive or, or, specific. Still 12% of these patients recur. But in patients that have received surgery, so in addition to getting scans, this is quite reassuring. If the ctDNA is negative and as far as the ctDNA is negative for a year after sequential analyzing the ctDNA, the likelihood of these patients to recur is like say 12%. So it’s quite reassuring.

Presently I’m using that for patients that even that they have received adjuvant chemotherapy or immunotherapy and it’s an additional way to the imaging to say, “The ctDNA is negative after a year,” so meaning the good news is that the likelihood of recurrence is really, really low. And I’m this patient has mentioned in the trial, those were high-risk patients.

Dr. Joaquim Bellmunt:

So the same for survival. Survival still is short so we cannot say that, but for disease-free survival, I think it’s very important to say,

Dr. Joaquim Bellmunt:

“well, these patients that, that have had serial ctDNA testing, they have, this really having greatest utility than having only a landmark ctDNA testing.” So serial monitoring is to predict with patients after a year I my, my have chances to recur and these chances based on this trial is 12%.

Dr. Joaquim Bellmunt:

So this data lend increasing confidence that patients with high-risk muscle invasive who have persistent ctDNA negative status after cystectomy, maybe even thinking maybe spared from adjuvant treatment. So that’s something that we will see after analyzing the results of this trial.

Dr. Joaquim Bellmunt:

So that’s not the only trial, there has been other trials presented. So the VOLGA study is a study that is exploring combination of immunotherapy and ADCs, enfortumab vedotin. This was presented at ESMO 2024. And here again it was confirmed that patients who were ctDNA negative or who had ctDNA clearance, they had improved eventful survival, but patients having ctDNA positive with no clearance, those patients were abstained.

Obviously this trial is ongoing, still we don’t have the results, but in this trial they use a different platform. That’s something. The Natera Signatera was not used. They use a, a different way to identify DNA in blood, that is the methylation sequencing. So the methylation of DNA, the pattern of methylation can help us also to monitor cancer. It’s a different way. As mentioned there are different tests, the Natera Signatera, there are the Guardant, there are the GRAILs or so many different platforms.

Dr. Joaquim Bellmunt:

Another, another, trial that was reported, this was a single-arm trial, this was reported by the Danish. So patients with ctDNA positivity after surgery, they receive Atezolizumab and they report that 55% of patients converted to ctDNA negative meaning these patients that you didn’t know what to do, do I need to give adjuvant immunotherapies? The ctDNA help on deciding, “Okay, you need to receive immunotherapy.” And when receiving Atezolizumab immunotherapy being ctDNA positive, those patients became negative. So helping to identify patients that might, might benefit.

Dr. Joaquim Bellmunt:

And then the last news on the ctDNA has been being able to go back, rescue samples from the NIAGARA trial. And as you know, the NIAGARA trial is a trial that has been done and also not in high risk. It has been done in muscle-invasive bladder cancer. This trial was comparing the combination of chemotherapies, cisplatin, gemcitabine, plus durvalumab that is a PD-L1 inhibitor before surgery. Here you can see the radical cystectomy, patients receiving four cycles before the surgery. This was compared with the standard of care that is giving neoadjuvant chemotherapy only. These patients randomized to each one of these arms, then they had the surgery, they receive some receive adjuvant durvalumab here or the others, sorry, the others didn’t receive anything. This trial was designed in 2016 where there was no role for adjuvant chemotherapy immunotherapy. There was role for nothing.

So this trial that you know now it is the, is the, has level one evidence. That’s the way that we need to treat patients with muscle-invasive bladder cancer. They need to receive chemotherapy and immunotherapy. Patients need to have an adequate renal function. There is also an option to give a split-dose platinum if they have more than 40 mLs per minimum. And this trial lead to a survival improvement in patients receiving chemoimmunotherapy followed by adjuvant immunotherapy after surgery. So what was presented at ASCO this year, and this was done by Tom Powles, is that the this plasma, they were able to collect plasma, sorry, this trial they were able to collect plasma before starting the treatment during the neoadjuvant period, plasma before cystectomy, and then plasma after cystectomy.

Dr. Joaquim Bellmunt:

And then what the this trial did show, as you can see here, the blue is the percentage of patients having ctDNA positive. This is baseline. Here is when they receive neoadjuvant chemotherapy. This is before radical cystectomy, the time of cystectomy, and then in the follow-up, post-radical cystectomy when they some of them they were receiving adjuvant. But as seen here is that we see that the percentage of ctDNA positivity, sorry, is going down. So going down to 22% after neoadjuvant treatment, and then after surgery it’s going down to 9%. An interesting observation is telling here that patients that receive neoadjuvant chemotherapy plus durvalumab, the rate of decrease in the ctDNA from baseline to pre-surgery was higher, 39%, compared to patients receiving chemotherapy. Confirming also the value of adding immunotherapy in the neoadjuvant setting.

So this was a something to support that ctDNA is helpful to identify benefit of drugs when this is in clinical trials.

Dr. Joaquim Bellmunt:

So also, the clearance did show a higher benefit patients that the ctDNA disappear while being on this neoadjuvant trials.

Dr. Joaquim Bellmunt:

And we see here in the post-cystectomy, the ctDNA detection was prognostic. So the same that we have seen before. So ctDNA is helpful in terms of prognosis, helpful on… The rate of decline is telling us that the patients are going to do much better than those that you don’t see a decline. And obviously now the ctDNA is built in several different trials.

Dr. Joaquim Bellmunt:

So here is the Alliance adjuvant trial. So trying to improve outcome in our patients having massive invasive bladder cancer. And as you can see here, the ctDNA is implemented before deciding to give adjuvant. You can see here that patients that have ctDNA positive here are randomized to the standard that is Nivolumab or an intensified adjuvant therapy that is Nivolumab plus Relatlimab. And also patients that are negative, this obviously these patients are high risk, are randomized to immediate treatment Nivolumab or surveillance, monitoring the ctDNA, and in case the ctDNA becomes positive, receive Nivolumab.

I know that is a complicated trial the first time that you see that, but this trial will further confirm the value of using ctDNA on deciding, for example, if you need to intensify the adjuvant therapy or if you need just to only monitor patients and treat at the time that the ctDNA is coming positive. So saying that we can like save treatment options for patients, you don’t need to treat these patients that are maybe continuously negative, or maybe you need to treat anyhow patients with ctDNA with Nivolumab. So it’s exploring trying to answer several questions. This trial is accruing and hopefully it’s going to provide some, some new inputs on the way to use the ctDNA.

Dr. Joaquim Bellmunt:

So I think that we are on time. So that’s my last slide. This is summarizing everything that I have been presenting. So those are the different settings where the ctDNA could be used. So yeah, you could see here the setting where now all these tools are being used for early detection for screening. I have not discussed, but also the urine ctDNA can be used to monitor recurrence in patients with non-muscle-invasive bladder cancer. So urine is also a place where we can check the DNA. And here we have said we can like follow the ctDNA to see the kinetics under treatment, follow after surgery if the ctDNA is coming negative. And in when patients unfortunately they develop metastatic disease, we can detect relapse even before that is evident by imaging. We can monitor if there are like changes on the, on the genomics and implement or changing therapy based on the findings that we see on ctDNA with… As mentioned, there are different platforms just to do all these things. So with that

Dr. Joaquim Bellmunt:

I would like to thanks Stephanie and BCAN for the opportunity to invite me to share all these data and I’m open to questions if I am able to answer because, as mentioned, this is an emerging area in bladder cancer and other tumors. So thank you very much for your attention.

Stephanie Chisolm:

Thank you. That was so comprehensive and detailed. I absolutely appreciate it. We actually had a number of very excellent questions that I’ll be asking you. I just think it was just wonderful that you know we now have this tool to use at baseline to check post-neoadjuvant chemotherapy and then also to be used for surveillance. You know, in terms of if a patient were to ask, what would you tell them in you know in terms of using this test, could that make them feel more confident in their treatment by being able to monitor? Is that something that you use to tell patients an idea that you use to get patients to consider this?

Dr. Joaquim Bellmunt:

Yeah, so obviously this is still not yet in the guidelines of and what I’m going to talk is trying to move ahead of the guidelines. So all the times we, we have new data that is you need to implement and explain the patients just before it’s approved by FDA, whatever. But yeah, I think, I think I need to congratulate Natera because it’s helping patients to get this tests done. I’m not doing marketing, but it’s really… Patients need to forget about the issues with the insurance and so on. So obviously there are like limitations on the number of tests that you can use, it need to be done beyond six to eight weeks. But for example, I can tell you a clinical case.

So a real patient, he received it wasn’t an upper tract tumor, so he received surgery and then he received adjuvant therapy. He was a high risk patient and imaging was a negative. And he came to me after adjuvant and said, “Well, what can I do to make sure that this tumor is not coming back? How can we detect earlier if this tumor is coming back and add for example, immunotherapy?” “Oh, it’s not a standard.” Well they say, “Or something else that could help me.” And this patient now has had this Natera platform being performed every, every eight weeks. Now it’s one year so and the patient is pretty comfortable saying, “well, imaging is negative.” Obviously we don’t skip imaging. But also when he receive… He all times call me, “Oh, because” and he received the results before me. So that’s amazing, so because the company is providing these results for patients that are anxious obviously to know these results and this patient after a year.

So I present this lecture that I get at SUO and say, “Now after a year you have only the chances of recurrence based on this clinical trial is only 10%, 12%.” So and he was quite relieved saying, “At least my ctDNA is not coming positive.” It’s an additional tool to reassure that things are going well.

Stephanie Chisolm:

Thank you. So you’re there at one of the premier cancer institutes in the world, Dana-Farber Cancer Institute, and I know that many of our colleagues that are working at large academic centers are using these tests regularly. What would you say to patients who are being seen at the community level? How do they ask their doctors who may not be as involved in this process and understanding the benefit to find out if they could get this test even at the community level?

Dr. Joaquim Bellmunt:

Well I believe that in a patient that has had surgery that is not a really, really high risk and the patient is doubtful if to receive adjuvant treatment. So that’s a way to say, “Okay, you don’t want to receive.” We’ll see the results have been IMvigor011 are going to tell you, ask more about that. But if a patient say, “No,” it is reluctant and to convince the patient say, “Well, maybe if you don’t want, let’s monitor the ctDNA. But if the ctDNA is coming positive, that’s mandatory that you need to receive adjuvant therapy before the any imaging is coming positive.” So I think it’s a way to get to know more about the status of the disease. It’s like in fact we are checking for minimal residual disease that is not detectable by any type of imaging right.

Stephanie Chisolm:

Right so you can see it before it even shows up. So another question I’m sure many patients ask you, “Is this covered by my insurance and will it still be, do you have to pre-authorized to get this test done?” How does this happen in the real world?

Dr. Joaquim Bellmunt:

Yeah, I think in the, it’s pretty clear in the perioperative setting, this is what I have focused on that space, it’s pretty clear, the results are pretty clear that is prognostic predictive and it’s helpful to understand a bit more how the biology of the disease evolves. So and I haven’t had any big problem. I’ve mentioned that the company’s helping a lot on solving the issues with insurance. And even they say that sometimes they assume if the insurance is not paying because the priority is the patient and I need to congratulate them, just even they have a mobile way just to get the blood test done at home, the patient doesn’t need to go to the hospital. So I think that’s an advantage for the patient. Usually as mentioned, if you request this test in a frequency that is every two months, it’s likely that no one is going to complain if you explain the rationale.

So obviously we have talked in this perioperative space the surgery after surgery, but now we’ve done we have been collecting ctDNA in patients receiving bladder preservation, right. And that’s very important. Say, “well, you give you chemotherapy or you give chemoradiation therapy, and you know you get imaging, you get cystoscopies, and you are never sure if still there is some cancer tumor cell hidden in the thickness of the bladder right because you have not removed the bladder.” And that’s a you see these changes in the bladder, there is bladder wall thickening. Sometimes the MRI is saying there is a highlight in this bladder, is the ADC is high, is there inflammation, is tumor? In these cases, I think ctDNA even it’s not standard, but we are now using that in patients that are willing to preserve their bladders, saying, how can you make sure that… Because imaging has limitations in patients that have received chemoradiation therapy, how can we optimize and make imaging…

Obviously we’re not going to make decisions with the ctDNA only in these cases, but like close follow up or additional measures intensifying biopsies just to go to areas where initially you would say, “Oh, let’s wait for three months.” Patients don’t like that, no one likes just to wait three months to know if things change, right. With that maybe you can get more information and to make decisions. That’s, that’s a setting that I think is emerging. And even there are now trials designed to preserve the bladder based on the negativization of the ctDNA before deciding, deciding to preserve the bladder. So a patient is coming say, “well, standard of care is neoadjuvant chemotherapy, removing your bladder,” but obviously no one wants the bladder to be removed despite neobladders, whatever.

So, and if you are asking for bladder preservation, you can say, “Well, this patient has responded pretty nicely to the neoadjuvant chemotherapy, but is there something else that might help?” And despite the RIT-URVT and so on. And if a patient has negativity on ctDNA with response on the RIT-URVT, maybe you can consider this patient for bladder preservation and not remove the bladder. This is going to be explored in a clinical trial. So that’s that’s the future of how we can use ctDNA.

Stephanie Chisolm:

So I have a really excellent question from a patient. “I’m four years with no evidence of disease after having muscle invasive disease and having my bladder and prostate removed in 2021 based on traditional CT scan of the chest, abdomen, pelvis contrast. Is it possible to start using ctDNA for ongoing surveillance instead of the traditional CT scans? How do I get the DNA profile from my original small cell carcinoma? Would that be stored in my doctor’s file?” So that’s really a question about is it possible to do tumor-informed even if you don’t have the actual bladder with the tumor, or does he need to just look at tumor-naive tests?

Dr. Joaquim Bellmunt:

Yeah, so I don’t know, this might be a patient of mine maybe because I have the same patient, same patient. It was a young patient with small cell that nothing has been exploring in this setting. This patient received chemotherapy and immunotherapy and then had surgery, and then after two and a half years or three years of follow up, the patient came to me and said, “well, can I check my ctDNA?” I said, “You need to know the natural history of the disease, right.” So initially we know that the median time to disease recurrence is like 18 months or 20 months, maybe now with the chemotherapy is, is more, but if you have been three years without disease progression so and everything has been negative, so continue with imaging likely it makes sense.

Going back to ctDNA it’s not a perfect tool. That’s the other thing. So it’s sensitive but it’s not 100% sensitive, not 100% specific. So and then the rationale is in a small cell lung cancer, if the patient is free of disease four years, I think there is no role. Obviously you want to explore more, but I haven’t seen in my life. Everything is possible in medicine obviously, but I haven’t seen very few patients like progressing after three years from muscle invasive. Maybe they develop a new tumor, that’s a different thing. But from the same tumor it’s exceptional to see recurrences. There are cases.

So I think that you could discuss with the oncologists and say, “Was my tumor really, really high risk? I received resistance therapy. There is still residual mass that we don’t know.” But after five four years in a small cell likely you are… You never, you never use that free of disease or cure right. Meaning I wouldn’t be like supporting that, but obviously it’s a way to say, “well, let’s add on,” but not it’s not going to exclude doing imaging. Imaging is the standard of care. That’s the important thing here. I don’t know if I answered the question, I know that… So happy, happy offline just to answer more detail.

Stephanie Chisolm:

No, there’s there’s so many good questions that are in here and a lot of them, you’ve covered so much in your webinar, so I’m not going to answer ask all the questions. In terms of looking at the difference between, again, tumor-informed, tumor-naive, you were talking about urine tests before. I mean for people with non-muscle invasive that aren’t necessarily having a tumor that they could see present. And if they didn’t have the tumor tested when they had that TURBT, what could be what would be the preferred type of CT testing for them at that stage if they still have their bladders?

Dr. Joaquim Bellmunt:

Well so all the times, that the good thing of these Natera is that you can go back and the tumor that was resected, you can use it with germline, that germline is the regular blood, right and create a customized customized platform to monitor. But this is in blood. In the urine, in the urine obviously there are different other ways to capture ctDNA, these and these methylation tests sometimes are much more useful or like tumor-informed tests looking for a panel of mutations. We know that non-muscle invasive is enriched for FGFR3. So there are customized panels that are exploring specific genes that are frequently mutated and you are looking in this urine, the presence of these DNA with these mutations or alterations. So those are areas that are actively being explored.

Important thing that we need to remember. So the urine need to be well-collected. So there’s a lot of contamination. There are like there are specific straight tubes, so you cannot collect the urine with a regular tube because you want to have the DNA well-preserved. And those are nuances that I have not I haven’t covered obviously, but that’s important. So these need to be done in a place where people is expert and know how to handle all these samples because, yeah, there might be false positives. So, but nowadays in patients that have received treatment for non-muscle invasive, in addition to the cytology and the FISH test. So also the urine DNA has been proven like helpful. But this is research still, we are not we’re getting there. So hopefully we’ll get there.

Stephanie Chisolm:

Yeah. So again, they’re looking for very different things when they’re looking for ctDNA than when they do this cytology test. With urine cytology, they’re actually looking for the cells, whereas you know from what I understand, they’re looking actually now for the actual DNA, not necessarily for the cells to see if there’s any evidence of those mutations that are common in, in this. Okay, great.

Dr. Joaquim Bellmunt:

Usually, usually you do the same as in blood. So the urine, you centrifuge the urine, the pellet is used to look for cytology, and the supernatant is the one that might contain the DNA, the tumor DNA, and this is what it gets processed. You extract the DNA and then you analyze if these DNA has a the specific mutations with the test that you’re looking your using.

Stephanie Chisolm:

This is really, again, amazing. Let me just ask you to end with just one general thing. What would be one fact you want to impart on all of the patients that are here, we have over we’ve had close to 100 people on this call today, really looking at what do you see as the future of bladder cancer because of this growth of ctDNA understanding?

Dr. Joaquim Bellmunt:

Yeah, I think, I think it’s here to stay, the ctDNA. So as mentioned, this is what I said, I said there are different platforms and the platforms are improving. So I met with a some people at Natera said well now “We are now developing platforms that instead of these 16 like bespoke mutations, we are looking for like 80 or maybe 700,” meaning the sensitivity and specificity is going to increase with this test. Obviously we need to study in the proper place and like these trials I have mentioned. So this trial was crazy, the IMvigor011, because it was the time that the Nivolumab and Pembrolizumab were approved here in the US, but this, this trial could only be completed in places where people didn’t have access to nothing. And then at least they were able… And it was randomized 2:1, meaning at least let’s let’s benefit as maximum as possible patients.

So yeah, it was a painful trial if you see from now, right because it was… Now wouldn’t be ethical, but it’s what the regulatory authorities require right. And now maybe this is going to change or establish in your standard of care in patients with the ctDNA. And as mentioned, we are going to hear that like this year. Sorry, I cannot say more the result of this trial. But no, no, I think that the the field is evolving. I mentioned just briefly that there are all… So you look for methylation DNA, you can look for mutations, you can look for epigenetic marks.

So now we are able, because whenever the DNA is shedding the blood. So usually the DNA is wrapped to the nucleosomes, and what can be captured is the nucleosome. So when there are the nucleosomes are the ones that regulate the opening or closing of the chromatin. And now we are able to capture that. We have what we call histone marks. So you are able to precipitate the histones and then you can read what’s the DNA that is in between these histones and say, “well this specific transcription factor, this gene is presenting this patient.” So it’s the techniques are evolving. Yeah, it’s amazing. It’s amazing really. It is difficult to follow. I can tell you, so.

Stephanie Chisolm:

It’s just been a very exciting, exciting time for bladder cancer. There are more treatments now available. Again, because we know more about these tumors down to that microscopic DNA level where we know what’s going to work. It can certainly help prevent patients from having expensive treatments that might not offer any benefit by understanding more about how those tumors need to be treated. So what is your recommendation? Like how long do people need to keep getting this test? Maybe if you have five years of nothing, is, what’s the what’s the option? What do you think it should be going forward? Should they be tested every year, every other year? How often do you have these tests done?

Dr. Joaquim Bellmunt:

So nobody knows. Now, as mentioned, as mentioned, nowadays what I do is like if the patient has received, depending on the type of treatment, if you say, well, the median time to, to, for disease recurrence in this trial is like 18, 20 months. I said, well, let’s go beyond that point. Maybe let’s test for two years, three years, but it doesn’t make sense to test beyond five years, for example, right? Because, so all I, this need to be linked to the biology of the disease, the type of treatment receive, because personally we don’t have rules on what’s the best frequency to test these patients. As mentioned the in these trials, we were testing every six, eight weeks. That was the timeframe. The technology is very important. So if anyone is interested, we present these data at ASCO. There is an educational chapter that I am happy to share with whoever that explains all these nuances on processing different types of tests. So that, yeah, I don’t have time just to go through because it’s a bit complicated.

Stephanie Chisolm:

Great. Thank you so much. I really think this has been a very informative program. I know that our patients are really going to appreciate having this as a tool.