Dr Elnair Discusses Richter's Transformation Outcomes for Patients With CLL/SLL

Radowan A Elnair, MD, Division of Oncology and Hematology, University of Nebraska Medical Center, Omaha, Nebraska, discusses a study on the outcome of Richter’s transformation in patients with chronic lymphocytic leukemia (CLL) and small lymphocytic lymphoma (SLL).

Transcript

My name is Radowan Elnair. I'm a Hematology and Oncology Fellow at University of Nebraska Medical Center in Omaha, Nebraska.

Richter's transformation is a rare complication in patients who have CLL or SLL. Most of the data we have in terms of outcomes and incidence of Richter transformation come from retrospective studies that were somewhat limited by the small numbers and the retrospective nature, the fact that they were either single-institution or multi-institutional, but still had some referral bias.

The goal of our study was to look at a big data set, a database that's going to have more number of patients with, hopefully, less referral bias and to hopefully address the incidence and the outcomes more appropriately.

In our study, we used the SEER database. We looked at the time period between 2000 and 2016. We used the ICD codes to identify patients who were diagnosed with CLL/SLL and then had a transformation event. We used the ICD codes for DLBCL or Hodgkin lymphoma. Those are the 2 histologies described to occur in patients with Richter's transformation.

As a comparison to those patients who had Richter transformation, we also identified patients who had de novo DLBCL, so DLBCL without a preceding diagnosis of CLL/SLL. We compared the outcomes of those with Richter's transformation to those who had DLBCL as a de novo event.

What we found in the outcomes was that out of more than 74,000 patients who had CLL or SLL, 530 patients developed Richter's transformation. That's corresponding to an incidence of 0.7%. Those transformation events, 85% of them were to a DLBCL and 15% were to a Hodgkin lymphoma.

The outcomes for either histology in the transformation event was equally as bad. The median overall survival (OS) was 10 months for the entire population with a Richter transformation.

We did identify a couple of factors as predictors for worse outcome occasions with Richter transformation. Those were an advanced Ann Arbor stage, so those with a Stage III or IV disease, and those who were previously treated for CLL that appeared to do worse when developing a Richter's transformation.

When you compare these outcomes to the outcomes of patients who had de novo DLBCL, within the SEER database, patients with de novo DLBCL had a median OS in the same time period of 62 months.

The biggest take-home message from this study—which is obviously limited by its retrospective nature, the fact that it did not include central pathology review—is we don't have any data for the clonality of the DLBCL transformation events.

The highlight from this study is that the outcomes are truly poor for patients with Richter transformation. It is truly an extremely rare event in patients with CLL and SLL. This highlights that those patients should be treated at centers with high volumes, centers that have clinical trials available.

Some of the studies that are currently ongoing to treat these patients use novel agents such as venetoclax, the BCL2 inhibitor. Some other studies are looking at the use of BTK inhibitors and PI3 kinase inhibitors, checkpoint inhibitors. That's certainly the way to go in those patients because it does seem like traditional treatment is associated with fairly poor outcomes.

Dr. Elnair said he would like to thank his collaborators on this project, Valerie Shostrom, Drs. Kallam and Ellithi, and Dr. Bociek for his mentorship.