 The induction therapy consists of 6 cycles of a CHOP chemotherapy in combination with Rituximab. If the mantle cell lymphoma is progressive after 4 cycles of chemotherapy, patients will be taken off study. Patients achieving at least a partial remission after 6 cycles R-CHOP will proceed to intensified consolidation Dexa-BEAM with stem cell collection and subsequent myelo-ablative radio-chemotherapy TBIHigh Dose Cyclophosphamide with autologous stem cells transplantation 