ASCO Expert on the Study of Autologous Transplantation in Relapsed DLBCL

Nirav Niranjan Shah, MD, discussed the study of patients with relapsed diffuse large B-cell lymphoma achieving only a PET/CT positive partial remission and what it means for this patient population.

Findings presented at the 2020 American Society of Clinical Oncology (ASCO) Virtual Scientific Program suggested that in patients with relapsed diffuse large B-cell lymphoma (DLBCL) achieving only a PET/CT positive partial remission, autologous stem cell transplantation should remain the current standard of care.

In an interview with CancerNetwork®, Nirav Niranjan Shah, MD, of the Medical College of Wisconsin, discussed the study and what it means for patients with DLBCL.

CancerNetwork®: Can you explain the study design for the study of autologous transplantation in patients with relapsed DLBCL achieving only a PET/CT positive partial remission?

Shah: So, this was a data analysis using the CIBMTR, so the Center of International Bone Marrow Transplant Registry. And so, it's a retrospective data set that allows us to look at patients who have undergone autologous stem cell transplant. And we specifically looked at a particular patient population, those who have diffuse large B-cell lymphoma, and then we stratified it further looking for a very particular population. Those who at the time of relapse and time of autologous transplant had chemosensitive disease, but also had a PET scan that showed that they were in a partial response before the autologous stem cell transplant.

What were the key findings from the analysis?

So, we wanted to look at this population of patients who went into their transplant with a partial response, really to understand: is there a role for autologous stem cell transplant for this patient population in the CAR T-cell era? What we found through the registries was that the number of autologous stem cell transplants done for diffuse large B-cell lymphoma had decreased 45% from 2017 to 2018. This made us think that there might be some patients like this who had a PET-CT partial response that didn't go to auto transplant, but probably got CAR T-cell therapy instead. And so, we wanted to see what the outcomes for autologous transplant look like. What we found in our study was that the 5 year progression-free survival, whether you relapsed early within 12 months of diagnosis or relapsed late, the progression-free survival was 41% at 5 years for both cohorts, and we were encouraged by this number and it does show that autologous transplant does still have a role for patients with chemosensitive relapsed diffuse large B-cell lymphoma, even if they have only a partial response at the time of transplant.

Given these findings, what would you say are the overall implications of this analysis?

Yeah, so I think the most important finding that I take away from this is that until we have randomized controlled trial data that shows that CAR T-cell is superior to autologous stem cell transplant in this specific patient population, that autologous transplant is the standard of care. Obviously, if you have chemo-refractory disease, well, that's a different patient population and those patients should be receiving CAR T-cell therapy. But I think we more need more data before we outright say that autologous transplant is no longer the most appropriate therapy for that particular population.

Are there any sort of next steps for this analysis?

So, we hope to publish our analysis and get it into a peer reviewed journal, so that it becomes available and I think this will be a study that becomes a benchmark that can then be used as a comparator for other clinical trials. I think this gives us a very interesting viewpoint of contemporary data, where PET-CT was used, which is often, you know, a lot of older studies don't utilize PET-CT. So, I think this will be a study that's a benchmark and can be used as a comparison to new therapies that are coming down the road. Because since, you know, the 1980s 1990s, autologous transplant has been that standard of care for relapsed aggressive B-cell lymphoma. And this supports that it should remain that. But it's also possible that over time new therapies do improve upon autologous transplant. But I think this trial will be a nice sort of benchmark to use for future studies.

Is there anything that I didn’t ask you that you think is worth mentioning?

You know, the other major finding we found is that the overall survival did favor patients who had late chemotherapy failure. So that was a finding that we saw in our multivariate analysis, but besides that point, there was no difference in transplant related mortality rates of relapse or progression. And there's no difference in progression-free survival, which were the other endpoints of our analysis.