B-chronic lymphocytic leukemia showed triple transformation, to diffuse large B cell, CD20-negative, and T-cell neoplasm during ofatumumab treatment: a case report

Are we closer to a standard of care for Richter's syndrome? Novel treatments on the horizon

INTRODUCTION

The therapeutic landscape for chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) has significantly evolved over the past decade with dramatically improved outcomes with the introduction of targeted therapies. This unfortunately has not been the case for Richter transformation (RT), the histologic transformation to a more aggressive lymphoma, most typically diffuse large B-cell lymphoma (DLBCL). As such, RT continues to be one of the most challenging complications of CLL/SLL. Historically, RT has a poor response to treatment, with a minority reaching complete remission (CR) and overall survival (OS) being less than a year.

AREAS COVERED

The focus of this review is to discuss the effectiveness of commonly used regimens, and review existing data for emerging regimens being examined in ongoing clinical trials to improve prognosis and outcomes in patients with RT. Despite extensive efforts to optimize therapies for RT, there is still no generalized consensus on either first-line treatment regimens or regimens in the relapsed/refractory setting. RT continues to carry a high mortality rate without durable response to current therapeutic agents.

EXPERT OPINION

Ongoing and future research may identify novel treatment approaches that will eventually improve outcomes for patients with RT. The optimal care for RT patients is a clinical trial, when feasible.

Treatment of Richter Transformation of Chronic Lymphocytic Leukemia in the Modern Era

Richter Transformation (RT) refers to the development of an aggressive lymphoma in the setting of chronic lymphocytic leukemia (CLL). While many variants of RT are recognized, diffuse large B-cell lymphoma (RT-DLBCL) is the most common (80%), followed by Hodgkin’s lymphoma (RT-HL, 19%). Diagnosis is based upon histologic evaluation of clinically suspicious lymph nodes. Positron emission tomography (PET) may be used to select the node of interest for biopsy. Although clonality testing is not a prerequisite of RT diagnosis, it has significant implications for survival. Clonally related DLBCL carries the worst prognosis with a median overall survival (OS) of less than one year in the era of combination chemotherapies with or without anti-CD20 antibodies. Prognosis has improved with the use of stem cell transplant and newer agents such as targeted therapy and newer forms of immunotherapy. Consideration of a clinical trial is encouraged. This review describes our current understanding of RT and focuses on treatment of RT-DLBCL, including clinical trials in progress and new therapies in development. We also report an illustrative example of a patient with clonally related DLBCL who survived two years after diagnosis without the use of combination chemotherapy.

Richter's syndrome of T-cell lineage (T rex lymphoma)

By definition, Richter's syndrome represents the transformation of low-grade B-cell lymphoma into high-grade B-cell lymphoma, usually refractory to treatment. Exceptional cases of transformation into very aggressive mature T-cell lymphomas have been described as an unusual manifestation of the syndrome in patients died after few months from the diagnosis, despite chemotherapy. The time is ripe to regroup these T lymphomas under a new pathological subset, through the unequivocal alternate naming of 'T rex lymphoma', by analogy with the aggressive behavior of the famous dinosaur (T. rex). In practice, it represents the transformation of low-grade B-cell lymphoma into high-grade T-cell lymphoma, burdened by a very poor prognosis, because of the underlying B-cell lymphoma, which negatively interferes with the immune response of the patient. Against this distinct lymphomatous T clone, the major therapeutic efforts should be addressed.

Peripheral T-Cell Lymphoma Arising in Patients With Chronic Lymphocytic Leukemia

OBJECTIVES

To describe three further cases of anaplastic large cell lymphoma (ALCL) occurring in patients with preexisting chronic lymphocytic leukemia (CLL). We also reviewed the literature of previously published cases.

METHODS

We discuss the clinical features, histopathology, and outcomes for three patients with ALCL and CLL from Perth, Australia. The cases were also included in a literature review of existing cases and comparisons were made with our cohort.

RESULTS

The three patients included two men (aged 77 and 74 years) and one woman (aged 66 years). All had a history of untreated CLL with diagnosis established 4 to 16 years before. They had lymphadenopathy and/or cutaneous/soft tissue lesions that proved to be ALCL, ALK+ (one case) or ALCL, ALK- (two cases).

CONCLUSIONS

Further research is required in this area to establish prognostic and management recommendations. Increasing numbers of cases are being described. Positron emission tomography with computed tomography was not useful in our cohort for diagnosing progression.