Rituximab and/or Lenalidomide in Treating Patients With Follicular Non-Hodgkin’s Lymphoma That is Not Refractory to Rituximab

Documentation of Disease

Previously treated, histologically confirmed follicle center cell lymphoma, World Health Organization (WHO) classification, grade 1, 2, or 3a
Institutional flow cytometry or immunohistochemistry must confirm Cluster of Differentiation 20 (CD20) antigen expression.

Prior Treatment

Patient must have been treated with rituximab either alone or in combination with chemotherapy.
Patient must have a time to progression of ≥ 6 months from last rituximab dose.
No corticosteroids within two weeks prior to study, except for maintenance therapy for a non-malignant disease. Maintenance therapy dose may not exceed 20 mg/day prednisone or equivalent.
No prior radioimmunotherapy within 12 months of study entry.
Age ≥ 18 years.
Eastern Cooperative Oncology Group (ECOG) Performance Status 0-2.

Measurable disease must be present either on physical examination or imaging studies. Non-measurable disease alone is not acceptable. Any tumor mass >1 cm is acceptable.Lesions that are considered non-measurable include the following:

Bone lesions
Ascites
Pleural/pericardial effusion
Lymphangitis cutis/pulmonis
Bone marrow
No known Central Nervous System (CNS) involvement by lymphoma.
No known Human Immunodeficiency Virus (HIV) infection.
Non-pregnant and non-nursing.
Patients with a "currently active" second malignancy, other than non-melanoma skin cancers, are not eligible.
Patients with a recent history (within 3 months of study entry) of Deep Vein Thrombosis/Pulmonary Embolism (DVT/PE) are not eligible.

Required Initial Laboratory Values:

Absolute Neutrophil Count (ANC) ≥ 1000/µL
Platelet count ≥ 75,000/µL
Creatinine < 1.5 x Upper Limit of Normal (ULN) unless attributed to lymphoma or calculated clearance > 50 mL/min (patients on dialysis are not eligible)
Total Bilirubin ≤ 2 x ULN unless attributed to lymphoma or Gilbert's disease