Inclusion Criteria

Inclusion Criteria selected:

- Histologically verified diagnosis if MALT lymphoma of any localization

- Measurable disease upon diagnosis or first or greater relapse after local therapy,
prior chemotherapy orHP-eradication. In addition, also in patients with gastric
MALT-lymphoma judged refractory to HP-eradication by a minimum follow-up of 12 months
after successfulHP-eradication will be included in the study. Patients with gastric
MALT lymphoma and no evidence of HP-infection may be enrolled immediately

- Ann Arbor Stage I-IV

- In case of prior treatment with Rituximab, the presence of CD20 on lymphoma cells
must have been demonstrated before inclusion in the trial.

- ECOG performance status of 0,1 or 2

- Patient must be able to take aspirin daily as prophylactic anticoagulation (patients
intolerant to ASA may use warfarin or low molecular weight heparin

Exclusion Criteria selected:

- Lymphoma histology other than MALT lymphoma or MALT lymphoma with a diffuse large
cell lymphoma ("high grade lymphoma") - component

- Use of any investigational agent within 28 days prior to initiation of treatment with
lenalidomide

- History of malignancy other than squamous cell carcinoma, basal cell carcinoma of the
skin or carcinoma in situ of the cervix within the last 5 years

- Major surgery, other than diagnostic surgery, within the last 4 weeks

- Evidence of CNS involvement

- A history of uncontrolled seizures, central nervous system disorders or psychiatric
disability judged by the investigator to be clinically significant and adversely
affecting compliance to study drugs

- Severe peripheral polyneuropathy

- Clinically significant cardiac disease or myocardial infarction within the last 6
months

- Known hypersensitivity to thalidomide or lenalidomide or rituximab