A Study of MabThera (Rituximab) in Primary Central Nervous System Lymphoma.

An Open Label Study of the Effect of Rituxan, High Dose Methotrexate and High Dose Cytarabine on Response Rate in Patients With Primary Central Nervous System Lymphoma.

This study will evaluate the efficacy and safety of MabThera plus high dose methotrexate plus high dose cytarabine in patients with central nervous system non-Hodgkin's lymphoma. Eligible patients will receive a treatment regimen consisting of MabThera (750mg/m2 iv) plus methotrexate (8g/m2 iv) given at intervals up to week 22, plus cytarabine (2g/m2 iv) at week 11 and week 22. The anticipated time on study treatment is 3-12 months, and the target sample size is <100 individuals.

Inclusion Criteria:

• adult patients, 18-80 years of age;
• histological diagnosis of primary central nervous system lymphoma;
• B-cell proliferation verified by positive staining for CD20;
• >=1 measurable lesion.

Exclusion Criteria:

• prior chemotherapy, other than corticosteroids, >=6 weeks before and after diagnosis or surgery;
• history of prior cranial irradiation;
• evidence of plurisystemic non-Hodgkin's lymphoma;
• other active malignant disease (other than basal cell or squamous cell cancer of skin,or cancer in situ of cervix;
• uncontrolled active infection.