Richter's syndrome of the central nervous system diagnosed concurrently with chronic lymphocytic leukaemia: A case report and literature review.

Rationale: Central nervous system (CNS) infiltration of Richter's syndrome (RS) is rare and only a few cases were discussed. Of these published cases, either they were accompanied with lymph node involvement or with a history of chronic lymphocytic leukemia (CLL). To our knowledge, this is the first published case of RS of the brain and meninges diagnosed concurrently with CLL in the absence of any evidence of lymphoma outside of the CNS.

Patient Concerns: A 67-year-old female presented with slurred speech, headache, and left-sided hemiparesis. Magnetic resonance imaging of the brain revealed an irregular lesion 30 mm in diameter in the right parietal lobe. The mass was totally removed and pathology revealed diffuse large B-cell lymphoma (DLBCL) of non-germinal center type by Hans' classification. The patient's leukocyte count was 12.1 × 109/L (76.9% lymphocytes), and fluorescence-activated cell sorting (FACS) analysis of blood revealed a clonal B-cell population (36.75% leukocytes) corresponding to the immunological CLL profile (Matutes score of 5/5). Bone marrow (BM) aspiration and biopsy also indicated CLL. The analysis of immunoglobulin heavy chain gene (IGH) and kappa chain gene (IGK) in the patient's BM and CNS tissue indicated that the DLBCL of the brain was derived from the CLL clone.

Diagnoses: RS of the CNS diagnosed concurrently with CLL.

Interventions: The patient received intravenous chemotherapy (6.0 g methotrexate) and intrathecal chemotherapy (10 mg methotrexate, 50 mg cytarabine, 5 mg dexamethasone).

Outcomes: The patient returned to our department with left-sided hemiparesis and headache 2 weeks after the chemotherapy. Repeat MRI showed progression of the brain lesion. Her general condition deteriorated significantly with confusion and high fever, and she died within a few days at only 10 weeks after the onset of symptoms.

Lessons: The survival of CNS-RS patients is very poor and and is always complicated with multiple and different genetic alterations. Because of chemotherapy insensitivity, a multidisciplinary treatment including surgery and radiotherapy together with novel agents may be an option to improving patient outcomes.