Richters syndrome (RS), also known as Richters transformation, is a transformation of B cell chronic lymphocytic leukemia (CLL) or hairy cell leukemia into a fast-growing diffuse large B cell lymphoma, a variety of non-Hodgkin lymphoma which is refractory to treatment and carries a bad prognosis. There is also a less common variant in which the CLL changes into a Hodgkins lymphoma. Rarely, transformations to a form of myeloid leukemia have been observed. These extraordinarily rare transformations carry a very poor prognosis. Richters transformation affects about 5% of CLL patients at some point during their lives. Signs and symptoms
Symptoms of Richter’s transformation in a CLL patient include fever (without infection), elevated serum levels of lactate dehydrogenase, and rapidly enlarging lymph nodes. While about 8% of all CLL patients will have elevated levels of serum lactate dehydrogenase (LDH), more than 50% of CLL patients with Richters transformation will have elevated LDH levels.Richters can appear suddenly, even in patients who were in remission. Cause
A case of RS may have arisen by one of two different routes:  a transformation of the CLL cells into lymphoma, or the appearance of an unrelated lymphoma.It is thought that genetic defects may introduce the additional abnormalities necessary to transform CLL cells into Richters syndrome cells. Treatment
Treatment with conventional immunochemotherapy is usually indicated; in younger patients, allogeneic bone marrow transplantation may be curative. Prognosis
The prognosis is generally poor.
PMID 16710033. S2CID 25490586.