Freiburg ZNS-NHL Study

Inclusion Criteria: * group A: first diagnosis of PCNSL, histologically confirmed * group B: relapse or progression of PCNSL after MTX containing chemotherapy * age 18 - 65 years * not legally incompetent, physically or mentally incapable of giving consent * written signed and dated informed consent of the legal representative and - if possible - of the patient Exclusion Criteria: * manifestations of further lymphoma outside the CNS * sero-positive for HIV * severe pulmonary, cardiac, hepatic, renal impairment * neutrophil count \< 2.000/µl, platelet count \< 100.000/µl * pulmonary disease with IVC \< 55%, DLCO \< 40% * cardiac ejection fraction \< 50%, uncontrolled malign arrhythmia * creatinine \> 1,5 mg% or creatinine-clearance \< 50ml/min * bilirubin \> 2mg/dl * ascites or pleural effusion (\> 500ml) * pregnancy o r lactation * women with childbearing potential without sufficient contraception * participation in another clinical trial within the last 30 days prior to the begin or parallel to this study * known or current drug or alcohol abuse * known hypersensitivity against methotrexate, cytarabine, thiotepa, BCNU rituximab, leukovorin, dexamethasone, neupogen and neulasta.