Bendamustine Plus Rituximab Versus Fludarabine Plus Rituximab

Inclusion Criteria: * Patients with histological verified CD20-positive B-Cell-Lymphomas of the following entities: * Follicular lymphoma grade 1 and 2 * Immunocytoma and lymphoplasmocytic lymphoma * Marginal zone lymphoma, nodal and generalised * Mantle cell lymphoma * lymphocytic lymphoma (CLL without leucaemic characteristics) * non-specified/classified lymphomas of low malignancy * Recurrent disease (remission duration minimum 3 months), independent of type or quantity of prior therapies, except of Rituximab containing regimens, or if remission duration is \> 1 year after Rituximab containing regimen, or refractory to prior therapy (progression under therapy or during 3 months after completion), except refractory disease to purin analogs or Bendamustine * Need for therapy, except mantle cell lymphomas * Stadium II (bulky disease, 7.5 cm), II or IV * Written informed consent * Performance status WHO 0-2 * Histology not older than 6 months Exclusion Criteria: * Patients not establishing all above mentioned prerequisites * Option of a primary, potentially curative radiation therapy * Patients refractory to Rituximab containing regimens * Comorbidities excluding a study conform therapy: heart attack during the last 6 months severe, medicinal not adjustable hypertonia severe functional defects of the heart (NYHA III or IV) lung (WHO grade III or IV) liver or kidney (creatinine \> 2 mg/dl, GOT + GPT or bilirubin 3 x ULN, except caused by lymphoma * Active auto immunohemoly…