Rituximab and Bendamustine in Very Elderly Patients or Elderly Medically Non Fit Patients With Aggressive B-cell Lymphoma

Inclusion Criteria: * Histology: Diagnosis of aggressive CD20+, confirmed by an excisional biopsy of a lymph node or by a sufficiently extensive biopsy of an extranodal involvement if there is no lymph node involvement. It will be possible to treat the following entities in this study as defined by the new WHO classification of 2008: B-NHL, Follicular lymphoma grade IIIb,DLBCL, not otherwise specified (NOS),common morphologic variants: centroblastic,immunoblastic,anaplastic,rare morphologic variants.DLBCL subtypes/entities:T cell/histiocyte rich large B-cell lymphoma, primary cutaneous DLBCL, leg type, EBV-positive DLBCL of the elderly, DLBCL associated with chronic inflammation, primary mediastinal (thymic) large B-cell lymphoma, intravascular large B-cell lymphoma,ALK-positive large B-cell lymphoma, Plasmoblastic lymphoma, Primary effusion lymphoma, B-cell lymphoma, unclassifiable, with features inter¬mediate between diffuse large B-cell lymphoma and Burkitt lymphoma, B-cell lymphoma, unclassifiable, with features inter¬mediate between diffuse large B-cell lymphoma and Hodgkin lymphoma * Stage: Any stages according to Ann Arbor Classification * Risk group: All risk groups (IPI 1 to 5) * Life expectancy Life expectancy of at least 6 weeks, when lymphoma is treated * Age: Age elder than 81 or Age 61 to 80 and CIRS \>6 not qualifying for CHOP-therapy * Gender: any * Performance status: Performance status ECOG 0 - 3. The performance status of each patient is to be assessed at the time of registration which might be after the initiation of pre-phase treatment which, as experience has shown, can result in a significant improvement of the patient´s performance status. A definition of the performance status is provided in Appendix 25.6 * Ability to give informed consent * Written informed consent of the patient * Contract of participation signed by the study center and sponsor Exclusion Criteria: * Already initiated lymphoma therapy (except for the prephase treatment until first application of rituximab) * Serious accompanying disorder or impaired organ function (except when due to lymphoma involvement), in particular: Heart: angina pectoris CCS \>2, cardiac failure NYHA \>3; Lungs: the patient is to be excluded if the resultant pulmonary function test shows FEV1\<50% or a diffusion capacity \<50% of the reference values: Calculated creatinin clearance \< 10 ml/min (Cockcroft-Gault); Liver: total bilirubin \> 3 mg/dl; Uncontrollable diabetes mellitus (because of prephase treatment with prednisone!) * Platelets \<100 000/mm3, leukocytes \<2500/mm3 (if not due to lymphoma) * Known hypersensitivity to the medications to be used * HIV-positivity * Acute or chronic active hepatitis * Poor patient compliance * Simultaneous participation in other treatment studies * Prior chemo- or radiotherapy, long-term use of corticosteroids or anti-neoplastic drugs for previous disorder * Other concomitant tumor disease and/or tumor disease in the past 5 years (except basalioma of the skin and carcinoma in situ) * CNS involvement of lymphoma (intracerebral, meningeal, intraspinal) * Active serious infections not controlled by oral or intravenous antibiotics or anti-fungal * Any medical condition which in the opinion of the investigator places the subject at an unacceptably high risk for toxicities. * Non-conformity to eligibility criteria.