 Rituximab: If at the end of this period the patient still meets entry criteria heshe will be treated with rituximab, 375 mgm2 i.v. on days 1, 8, 15 and 22, with subsequent follow-up of at least one year. Patients will be retreated at month 6th once B-cells return to circulation and will be independent of the clinical status of the patient. B-cell return is defined as CD19B cell count 15microliter or 5 of baseline count. There will be a - 3 day window for each study visit, to account for weekends, holidays, and scheduling conflicts. 