Pembrolizumab Alone or With Idelalisib or Ibrutinib in Treating Patients With Relapsed or Refractory Chronic Lymphocytic Leukemia or Other Low-Grade B-Cell Non-Hodgkin Lymphomas

Inclusion Criteria

• CLL/SLL PATIENTS (ARM A) ONLY
• Diagnosis of CLL according to the National Cancer Institute (NCI) criteria or SLL according to the World Health Organization (WHO) criteria; this includes previous documentation of:
• Biopsy-proven small lymphocytic lymphoma or
• Diagnosis of CLL according to NCI working group criteria as evidenced by all of the following:
• Peripheral blood B cell count of > 5 x 10^9/L consisting of small to moderate size lymphocytes
• Immunophenotyping consistent with CLL defined as:
• The predominant population of lymphocytes share both B-cell antigens (cluster of differentiation [CD]19, CD20 [typically dim expression] or CD23) as well as CD5 in the absence of other pan-T-cell markers (CD3, CD2, etc.)
• Clonality as evidenced by kappa or lambda light chain expression (typically dim immunoglobulin expression) or other genetic method (e.g. immunoglobulin heavy chain variable [IGHV] analysis)
• NOTE: splenomegaly, hepatomegaly, or lymphadenopathy are not required for the diagnosis of CLL
• Before diagnosing CLL or SLL, mantle cell lymphoma must be excluded by demonstrating a negative fluorescent in situ hybridization (FISH) analysis for t(11;14) (immunoglobulin H [IgH]/cyclin D1 [CCND1]) on peripheral blood or tissue biopsy or negative immunohistochemical stains for cyclin D1 on involved tissue biopsy
• Patients must be previously treated with at least one prior line of therapy; EXCEPTION: CLL patients with Richter's transformation or Hodgkin transformation do not need prior therapy to enroll
• NOTE:
• Prior chemotherapy or biologic novel therapy or anti-cancer monoclonal antibody based therapy for treatment of CLL will be considered prior therapy; nutraceutical treatments with no established benefit in CLL (such as epigallocatechin gallate or EGCG, found in green tea or other herbal treatments) will not be considered "prior treatment"
• Prior oral corticosteroid therapy for an indication other than CLL will not be considered "prior treatment"
• Previous use of corticosteroids in the combination with other therapy for treatment of autoimmune complications of CLL does constitute prior therapy for CLL
• CLL/SLL patients must have progressive disease with any one of the following characteristics based on standard criteria for treatment as defined by the NCI-Working Group (WG) 1996
• Symptomatic CLL characterized by any one of the following:
• Weight loss >= 10% within the previous 6 months
• Extreme fatigue attributed to CLL
• Fevers >= 100.5 degree Fahrenheit (F) for 2 weeks without evidence of infection
• Drenching night sweats without evidence of infection
• Evidence of progressive bone marrow failure with hemoglobin = = 1.5 cm in diameter)
• LOW GRADE B-NHL PATIENTS ONLY
• Histologically confirmed relapsed (response to last treatment >= 6 months duration) or refractory (no response to last treatment or response duration = 1.5 cm in diameter) as detected by CT or the CT images of the PET/CT; NOTE: patients with Waldenstrom macroglobulinemia are not required to have measurable disease by CT or PET/CT if monoclonal protein is detectable by serum protein electrophoresis and/or immunoglobulin M (IgM) level is at least 2 times upper limit of normal
• CLL WITH RICHTER's TRANSFORMATION (ARM C) ONLY
• CLL diagnosis confirmed as have biopsy-proven Richter's transformation; NOTE: both untreated and previously treated patients in this category can be enrolled as long as measurable disease can be detected by PET/CT or CT (>= 1.5 cm in diameter)
• ALL PATIENTS
• Eastern Cooperative Oncology Group (ECOG) performance status (PS) 0 or 1
• Creatinine = = 60 mL/min for subject with creatinine levels > 1.5 x institutional ULN (obtained = = 25 x 10^9/L (obtained = = 0.5 x 10^9/L (obtained = 1.5 x ULN, a direct bilirubin should be performed and must be =< upper limit of normal (obtained =< 14 days prior to registration)
• Aspartate aminotransferase (AST) (serum glutamic oxaloacetic transaminase [SGOT])