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 immunohemolytic anemia (AIHA)

- HIV positive patients

- Active hepatitis infection

- Severe psychiatric diseases

- No compliance or non-compliance to be expected

- Pregnant or breast feeding women

- Anamnestic malignancies or secondary malignancies, not proven

- Cured/curable by surgery