Richter's syndrome presenting as a nasal lymphoma

Richter's syndrome (RS) is a high-grade large cell lymphoma arising in patients with B-cell chronic lymphocytic leukemia (CLL). The prognosis of RS is very poor and the development of RS is a serious complication of CLL. We present a case of a patient with a 4-year history of B-cell CLL who developed diffuse large B-cell nasal lymphoma. The patient exhibited good response to chemotherapy and irradiation and achieved complete remission. Five months later, the patient suffered leptomeningeal involvement and has been treated with repeated intrathecal chemotherapy. Leukemic cells of the patient expressed CD13. CD13+ CLLs have been reported to have an unfavorable prognosis and this case may support the view.