Primary CNS lymphoma: clinical presentation, pathological classification, molecular pathogenesis and treatment

Primary CNS lymphomas (PCNSL) represent malignant non-Hodgkin's B cell lymp homas, which are confined to the central nervous system. They show a dramat ic increase in frequency in the immunocompromised as well as in the immunoc ompetent population. Recent studies have identified germinal center B cells as the cellular origin of PCNSL; however, the: details of their molecular pathogenesis still remain to be elucidated. Treatment recommendations are n ot clearly established. Radiotherapy (RT) is efficient in terms of tumor re sponse, but not curative. Median survival after RT alone is about 1 year. A ccording to the results of uncontrolled studies the combination of RT and c hemotherapy based on high-dose methotrexate (HD-MTX) is most efficient in t erms of survival rates. However, long-term neurotoxicity overshadows treatm ent efficacy, especially in patients over 60 years of age. The authors favo r the systematic evaluation of chemotherapy alone with protocols including HD MTX, because unicenter results are promising in terms of both survival a s well as quality of life in long term survivors. (C) 2000 Elsevier Science B.V. All rights reserved.