Lenalidomide and Obinutuzumab in Treating Patients With Recurrent or Refractory Chronic Lymphocytic Leukemia or Small Lymphocytic Lymphoma

Inclusion Criteria: * Able to understand and to provide voluntarily informed consent * Have documented chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL) according to National Cancer Institute (NCI) criteria * Recurrent or refractory disease according to NCI criteria * Patient are eligible if they have received one or more prior treatment * Eastern Cooperative Oncology Group (ECOG) performance status of 0-2 * Life expectancy \> 6 months * Serum creatinine less or equal to 2 mg/dl * Total bilirubin less or equal to 2 mg/dl * Alanine aminotransferase (ALT)/serum glutamate pyruvate transaminase (SGPT) less or equal to two times the upper normal limit * Disease free of prior malignancies for 3 years with exception of currently treated basal cell squamous cell carcinoma of the skin, or carcinoma "in situ" of the cervix or breast; patients with malignancies with indolent behavior such as prostate cancer treated with radiation or surgery can be enrolled in the study as long as they have a reasonable expectation to have been cured with the treatment modality received * No prior history of myelodysplastic syndrome or other myeloid malignancy * All participants must be registered into the mandatory Revlimid Risk Evaluation and Mitigation Strategy (REMS) program, and be willing and able to comply with the requirements of the Revlimid REMS * Females of childbearing potential (FCBP) must have a negative serum and/or urine pregnancy test with a sensitive of at least 50 mIU/mL within 10-14 days and again within 24 hours prior to prescribe lenalidomide for cycle 1 (prescriptions must be filled within 7 days as required by Revlimid REMS) and must either commit to continued abstinence from heterosexual intercourse or begin TWO acceptable methods of birth control, one highly effective method and one additional effective method AT THE SAME TIME, at least 28 days before she starts taking lenalidomide; FCBP must also agree to ongoing pregnancy testing; men must agree to use a latex condom during sexual contact with a FCBP even if they have had a successful vasectomy Exclusion Criteria: * Known sensitivity to lenalidomide or other thalidomide derivatives or anti cluster of differentiation (CD)20 * Documented prolymphocytic leukemia (prolymphocytes more than 55% in the blood) * Known history of infection with human immunodeficiency virus (HIV) or human T cell leukemia virus 1 (HTLV-1) * Serologic status reflecting active hepatitis B or C; patients with hepatitis B (HBV) antibody positive but who have positivity for hepatitis B surface antigen (HBsAg) or anti hepatitis B core antibody (anti-HBc) and patients who are positive for anti-hepatitis C (HCV) will need to have a negative polymerase chain reaction (PCR) (viral HBV deoxyribonucleic acid \[DNA\] or HCV ribonucleic acid \[RNA\]) result prior to enrollment; those who are HBsAg positive or HBV DNA positive and those who are positive for HCV (RNA) will be excluded * Pregnant or breast feeding females * History of tuberculosis treated within the last five years or recent exposure to tuberculosis * Any serious medical condition, laboratory abnormality, or psychiatric illness that places the subject unacceptable risk if he/she were to participate to the study * Patients with a recent history of deep vein thrombosis or pulmonary embolus, in the six months prior to enrollment are not eligible for this study