Richter syndrome, also called Richter transformation, is described in the packet definition as the transformation of chronic lymphocytic leukemia into an aggressive non-Hodgkin lymphoma, usually diffuse large B-cell lymphoma. Occasional transformation to Hodgkin lymphoma has also been described, particularly in patients previously treated with purine nucleotide analogs. Prevalence is not certified in this packet.

No phenotype annotations are certified in this packet, and age of onset is not listed, so specific symptoms and their frequencies are unknown here. The condition is defined by a change in the behavior of an existing chronic lymphocytic leukemia into an aggressive lymphoma.

No causative genes and no inheritance pattern are certified for Richter syndrome in this packet. According to the packet definition, molecular genetic studies suggest that in approximately half of cases the lymphoma is clonally related to the underlying chronic lymphocytic leukemia, whereas in the remaining cases it probably represents a secondary, unrelated neoplasm.

Diagnostic methods are not certified in this packet, so how the diagnosis is established is not described here.

No FDA-approved treatments, orphan-drug records or foundational therapies are certified in this packet. This reflects the contents of the packet only and does not establish that no treatment options exist. Treatment approaches are therefore not described here.

Prognosis is not certified in this packet. No natural history or survival information is available here, and none is inferred.

ClinicalTrials.gov records in the packet indicate that studies involving Richter transformation are currently active. NCT07220187 is a Phase 3 SWOG Cancer Research Network trial in newly diagnosed Richter transformation that tests an added therapy alongside the usual treatment (recruiting, start date 2026-08-04). NCT04623541 is a Phase 1 Genmab safety and efficacy study in relapsed or refractory chronic lymphocytic leukemia and Richter syndrome (active, not recruiting, started 2020-11-25). NCT05388006 is a Phase 2 Mayo Clinic study of a three-drug combination in Richter transformation from chronic lymphocytic leukemia or small lymphocytic lymphoma (active, not recruiting, started 2023-01-05). Trial listings change over time, and the ClinicalTrials.gov search page provides current records.