 Inclusion Criteria: - Histologically proven mantle cell lymphoma or histologically proven diffuse large B-cell non-Hodgkins lymphoma NHL according to the REAL classification - Measurable andor evaluable disease - Previously untreated patients Exclusion Criteria: - Burkitts or B-lymphoblastic lymphoma - Central nervous system CNS involvement - Active infection requiring treatment with systemic anti-infectives within 72 hours of chemotherapy - Prior malignancy within the last 5 years - T-cell lymphoma or history of indolent lymphoma - Prior bone marrow or stem cell transplantation - Known sensitivity to E. coli derived drug products 