Improvements in the Treatment of Patients With MCL Over the Past Decade

Peter Martin, MD, Chief of the Lymphoma Program, Weill Cornell Medicine, New York, discusses treatment patterns and outcomes of patients with mantle cell lymphoma (MCL) in the United States over the past 10 years, the data of which were presented at the virtual 2021 American Society of Clinical Oncology (ASCO) Annual Meeting.

Transcript

Hi, I'm Peter Martin. I'm the Chief of the Lymphoma Program at Weill Cornell Medicine in New York. My colleagues and I were interested in how our patients with mantle cell lymphoma (are) actually treated in the United States. We have seen over the past decade a lot of significant improvements in the outcomes of patients with mantle cell lymphoma in clinical trials.

The real question that comes up though is, “How do the results of those clinical trials translate into practices that are using the therapies that are defined in clinical trials as they are defined. What are the outcomes that we're getting in those patients who are being treated outside of clinical trials, mostly in community practices in the United States?”

We used the de-identified database derived from electronic medical records in the Flatiron database with a statistician, who did an excellent job. We came up with a series of questions.

One, what are the patterns of care that are being used in the United States in these practices? Two, what are the outcomes of patients being treated in these practices? Three, how is stem cell transplantation being used, and what are the outcomes of patients who receive stem cell transplantation compared to patients who do not receive stem cell transplantation?

Separately, Dr. Gilles A. Salles evaluated the role of rituximab maintenance using the same de-identified Flatiron electronic medical record database, and those data are being presented at EHA.

What we found was that, in general, there was less use of standard treatment regimens that you might think would be a case. This could be a variety of reasons. One is there may be insufficient communication regarding what standard treatments should be used. That's one possibility. Another possibility is that the treatment regimens that are being developed may not apply to the broad set of people who develop mantle cell lymphoma in the United States, either related to comorbidy conditions, age, geography, or other socioeconomic factors.

As a researcher who spends a lot of time thinking about how to treat people with mantle cell lymphoma better, one of the take-home messages that I've learned from this study is that it doesn't make sense to develop a regimen that can't be administered broadly in the United States. There are a lot of good regimens.

If they can only be administered in academic settings, then we're really ignoring the majority of people with mantle cell lymphoma. As researchers, we can do a better job developing regimens that are applicable more broadly to people with mantle cell lymphoma. Those regimens should focus on practicability in addition to efficacy and safety.

Whenever you look at de-identified health record data, there's always a chance that there are some biases. For example, we don't have response rates. A lot of these factors could impact the results in one way or another, overcome that to some degree by having a large number, in this case, over 4,000 patients to start with.

But really, the key when you're looking at data like this is to trying to focusing on certain key questions and then to validate those questions in other databases, ideally, separate databases for different countries or different types of medical records. That's what we're hoping to do in the next step.

One of the findings that is most relevant from my perspective was we are finding that amongst patients who we defined, in this case, a stem cell transplant eligible — and there are debates about how that should be done. In those patients, we did not find a significant advantage through the use of stem cell transplantation.

Now, there are at least 2 ongoing large randomized clinical trials in the United States and in Europe that are evaluating stem cell transplant. Ultimately, if we are going to rule out stem cell transplantation in the world, we need to have the results of those clinical trials.

As we increasingly find large datasets like this one, Flatiron dataset, showing that there may not be an advantage to stem cell transplantation, I think as researchers, we need to start coming up with treatments that might be applicable to younger patients that don't use stem cell transplantation.

We need to be prepared to move forward with regimens that are reasonable, effective, and well-tolerated that maybe don't use stem cell transplantation so that when those large clinical trials read out, we're ready to take those trials into the next phase of large randomized trials.