Inclusion Criteria:

          -  Patients must have histologically confirmed solid malignancy or lymphoma that is
             metastatic or unresectable

          -  There is reasonable expectation of response to pembrolizumab or nivolumab, and one of
             the drugs is available from the commercial supply; this includes (but is not limited
             to) the following tumor types: melanoma, non-small cell lung cancer, renal cell
             carcinoma, squamous cell carcinoma of the head and neck, bladder cancer, and classic
             Hodgkin lymphoma

          -  The patient must have failed at least one line of standard treatment, with the
             following exceptions in which a PD-1 antibody is Food and Drug Administration (FDA)
             approved in the first-line setting:

               -  Melanoma patients

               -  Non-small cell lung cancer patients without EGFR or ALK genomic tumor aberrations
                  whose tumors have high PD-L1 expression (tumor proportion score [TPS] >= 50%) as
                  determined by an FDA-approved test

          -  Patients must give informed consent

          -  Prior chemotherapy, immunotherapy, radiotherapy or major surgery (including radiation
             therapy or surgery for treatment of brain metastases) must be completed at least 3
             weeks before study entry; prior PD-1 or PD-L1 therapy is acceptable

          -  Patients must have an Eastern Cooperative Oncology Group (ECOG) performance status =<
             2

          -  Hemoglobin > 8.0 mg/dL (without transfusion in the preceding 7 days)

          -  Platelets >= 70,000 /uL

          -  Total bilirubin within normal institutional limits (patients with Gilbert's syndrome
             must have a total bilirubin < 3.0 mg/dL)

          -  Aspartate aminotransferase (AST) (serum glutamic-oxaloacetic transaminase [SGOT]) =< 2
             X institutional upper limit of normal (ULN)

          -  Alanine aminotransferase (ALT) (serum glutamate pyruvate transaminase [SGPT]) =< 2 X
             institutional ULN

          -  Patients must have measurable disease, defined as at least one lesion that can be
             accurately measured in at least one dimension (longest diameter to be recorded) as >=
             10 mm by computed tomography (CT) scan, positron emission tomography (PET)/CT scan,
             magnetic resonance imaging (MRI) or caliper/ruler measurement by clinical exam; lymph
             nodes: to be considered pathologically enlarged and measurable, a lymph node must be
             >= 15 mm in short axis when assessed by CT scan; lesions that have been radiated in
             the advanced setting cannot be included as sites of measurable disease unless clear
             tumor progression has been documented in these lesions since the end of radiation
             therapy

          -  Ability to swallow pills

        Exclusion Criteria:

          -  Systemic immunosuppressive medications such as steroids; the following steroid
             formulations are permitted: intranasal, intra-articular, and inhaled steroids

          -  History of immune-related adverse event from prior immunotherapy treatment that has
             not improved to grade 0-1; subjects with grade 2 hypothyroidism and grade 2 adrenal
             insufficiency requiring continued medical treatment may enroll provided that they are
             asymptomatic and stable on their dose of hormone replacement

          -  Serious concomitant systemic disorders (including active infections) that would
             compromise the safety of the patient or compromise the patient?s ability to complete
             the study, at the discretion of the investigator, including active autoimmune disease
             requiring treatment within the past 30 days

          -  Any condition requiring systemic treatment with either corticosteroids (> 10 mg daily
             prednisone equivalents) or other systemic immunosuppressive medications within 14 days
             of study drug administration; inhaled or topical steroids and adrenal replacement
             doses < 10 mg daily prednisone equivalents are permitted in the absence of active
             autoimmune disease; patients are permitted to use topical, ocular, intra-articular,
             intranasal, and inhalational corticosteroids (with minimal systemic absorption)'
             physiologic replacement doses of systemic corticosteroids are permitted, even if < 10
             mg/day prednisone equivalents; a brief course of corticosteroids for prophylaxis
             (e.g., contrast dye allergy) or for treatment of non-autoimmune conditions (e.g.,
             delayed-type hypersensitivity reaction caused by contact allergen) is permitted

          -  Second primary malignancy, except those second primary malignancies that are not
             considered to be competing causes of death in the opinion of the treating
             investigator; examples include: in situ carcinoma of the cervix, adequately treated
             non-melanoma carcinoma of the skin, or other malignancy treated at least 5 years
             previously with no evidence of recurrence

          -  Patients with active, untreated central nervous system (CNS) metastases will be
             excluded from this clinical trial; patients who have brain metastases that been
             treated with radiation therapy or surgery will be required to have a washout period of
             at least 3 weeks prior to study entry, must be neurologically asymptomatic, and must
             not require systemic steroids

          -  Women of child-bearing potential and men must agree to use adequate contraception
             prior to the start of treatment, for the duration of treatment, and for 5 months after
             last dose of study treatment

          -  Patients with immune deficiency have impaired immune responses, therefore, known human
             immunodeficiency virus (HIV)-positive patients are excluded from the study