Inclusion Criteria:

• Histological or cytological diagnosis of non-Hodgkin's lymphoma
• Disease exclusively localised into the CNS at first diagnosis and failure
• Progressive or recurrent disease
• Previous treatment with HDMTX containing CHT and/or RT
• Presence of at least one target lesion, bidimensionally measurable
• Age 18 - 75 years
• ECOG performance status < 3 (Appendix 1).
• No known HIV disease or immunodeficiency
• HBsAg-negative and Ab anti-HCV-negative patients.
• Adequate bone marrow function (plt > 100000 mm3, Hb > 9 g/dl, ANC > 2.000 mm3)
• Adequate renal function (serum creatinine < 2 times UNL)
• Adequate hepatic function (SGOT/SGPT < 3 times UNL, bilirubin and alkaline phosphatase < 2 times UNL)
• Adequate cardiac function (VEF ≥ 50%)
• Absence of any psycological, familial, sociological or geographical condition potentially hampering compliance with the study protocol and follow-up schedule
• Non-pregnant and non-lactating status for female patients. Adequate contraceptive measures during study participation for sexually active patients of childbearing potential.
• No previous or concurrent malignancies at other sites with the exception of surgically cured carcinoma in-site of the cervix and basal or squamous cell carcinoma of the skin and of other neoplasms without evidence of disease since at least 5 years.
• No concurrent treatment with other experimental drugs.
• Informed consent signed by the patient before registration