High grade lymphoma of the cerebellum: a rare complication of chronic lymphatic leukaemia

Chronic lymphocytic leukemia with central nervous system involvement: report of two cases with a comprehensive literature review

Central nervous system (CNS) involvement is a rare complication of chronic lymphocytic leukemia (CLL) with varied outcomes. We contribute two additional cases of CLL with CNS involvement. The clinical course and response to treatment are described. All 78 previously reported cases of CLL with CNS involvement are presented in this comprehensive review of the literature. CNS involvement of CLL is a rare complication that does not seem to correlate with any evident risk factors. Resolution of CNS symptoms can often be accomplished with intrathecal chemotherapy or irradiation. Early detection and treatment may result in better outcomes in this rare complication.

Richter syndrome: biology, incidence, and therapeutic strategies

Richter's transformation denotes the development of high-grade non-Hodgkin lymphoma, prolymphocytic leukemia, Hodgkin disease, or acute leukemia in patients with chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma. A search of published articles in Medline (PubMed) and abstracts from professional meetings was performed. An electronic database search of patients with CLL at The University of Texas M. D. Anderson Cancer Center (Houston, TX) determined the incidence of Richter syndrome (RS) in patients with CLL between 1992 and 2002. RS occurs in approximately 5% of patients with CLL. The large cells of RS may arise through transformation of the original CLL clone or represent a new neoplasm. RS may be triggered by viral infections, such as Epstein-Barr virus. Trisomy 12 and chromosome 11 abnormalities are more frequent in patients with RS than in the overall population of patients with CLL. Multiple genetic defects, such as mutations of the p53 tumor suppressor gene, p16INK4A, and p21, loss of p27 expression, deletion of retinoblastoma, increased copy number of C-MYC, and decreased expression of the A-MYB gene, have been described. These abnormalities may cause CLL cells to proliferate and-by facilitating the acquisition of new genetic abnormalities-to transform into RS cells. Therapeutic strategies include intensive chemotherapy, monoclonal antibodies, and stem cell transplantation. The response rates range from 5% to 43% (complete response, 5-38%), and the median survival duration ranges from 5 months to 8 months. In conclusion, RS may be triggered by viral infections or by genetic defects. Current treatments are aggressive, but prognosis is poor. Novel curative treatment strategies are needed.

Progressive multifocal leukoencephalopathy with concurrent Richter's syndrome

Progressive multifocal leukoencephalopathy (PML) is a demyelinating infectious disease caused by the JC virus. It was originally described in patients with chronic lymphocytic leukemia (CLL). Richter's syndrome, or transformation to large cell Lymphoma, occurs in approximately 3% of patients with CLL, and carries a poor prognosis. We report a patient with documented PML and concurrent Richter's transformation outside the central nervous system. Before establishing a definitive diagnosis of PML, radiation therapy to the presumed lymphomatous brain lesion had been considered, raising the issue of whether stereotactic brain biopsy should be considered in every patient in a similar situation. Although this is likely a rare occurrence, patients with Richter's transformation documented at an extra-neural site and a brain lesion may benefit from the establishment of an infectious diagnosis which would influence therapy.