Isolated Richter's transformation of the brain.

Patients with B-cell chronic lymphocytic leukemia (CLL) have an increased risk of second malignancy and may develop diffuse large-cell non-Hodgkin's lymphoma (DLCL) also known as Richter's syndrome (RS). Only seven cases of isolated brain RS without evidence of systemic lymphoma have been reported to date. We describe a case of isolated DLCL of the brain in a 58-year-old female patient with a 3 year history of B-cell CLL. The patient presented with falls due to left leg paresis and showed non-specific neuroimaging findings. Brain biopsy confirmed the diagnosis of DLCL and CLL restaging failed to demonstrate evidence of RS outside the CNS. The patient was treated with whole brain radiation therapy and was discharged 4 weeks later on weekly rituximab infusions. This report extends the previous experience by providing a detailed clinical, neuroradiological and pathological description of isolated RS of the brain. Early identification and timely CNS directed treatment may alter morbidity and positively influence quality of life.