Inclusion Criteria:

- Histologically confirmed hematologic malignancy meeting 1 of the following criteria:

- High-risk acute myeloid leukemia meeting 1 the following criteria:

- First complete response (CR) and ≥ 60 years of age OR < 60 years of age
with high-risk cytogenetics as defined by CALGB OR high-molecular risk and
not eligible or willing to undergo myeloablative conditioning

- Second or later complete remission

- Not in remission but with < 5% blasts within 3 weeks of start of
conditioning chemotherapy for allogeneic transplantation

- Patients with a history of CNS involvement allowed provided disease is in
remission at the time of transplantation

- Patients with non-Hodgkin lymphoma who are candidates for allogeneic stem cell
transplantation will be eligible; patients who have relapsed status post
autologous transplantation are eligible as long as they demonstrate chemotherapy
sensitive disease; patients with a history of CNS involvement are eligible if
this aspect of the disease is in remission at the time of transplantation

- High-risk chronic lymphocytic leukemia (CLL), small lymphocytic lymphoma (SLL),
or primary and secondary B-prolymphocytic leukemia (PLL) meeting 1 of the
following criteria:

- del(17p13.1) disease that has been treated (may have been given as
consolidation therapy)

- Less than PR to chemoimmunotherapy or relapsed within 2 years of treatment

- Nucleoside analog refractory disease or disease that relapsed after two
prior regimens

- Patients with Richter (large cell) transformation allowed provided the
large cell component of the disease is in remission (< 10% large cells in
the bone marrow allowed)

- Patient has undergone an allogeneic stem cell transplantation using a
reduced-intensity or non-myeloablative conditioning regimen within the past 60 days

- At least 40% T-cell donor chimerism at day 30

- ECOG performance status 0-2 (Karnofsky 60-100%)

- Life expectancy > 3 months

- Myeloid engraftment with absolute neutrophil count > 1,000/μL and platelet count >
50,000/μL (after allogeneic hematopoietic stem cell transplantation [AHSCT])

- Total bilirubin normal

- AST and ALT ≤ 2.5 times upper limit of normal (ULN)

- AST < 3 times ULN after AHSCT

- Creatinine clearance ≥ 50 mL/min in stratum 1 or ≥ 30 mL/min in stratum 2

- DLCO > 40% with no symptomatic pulmonary disease

- LVEF ≥ 30% by echocardiogram or MUGA

- Not pregnant or nursing

- Negative pregnancy test

- Fertile patients must agree to use two acceptable methods of contraception (one
highly effective method and one additional effective method) or practice abstinence
for ≥ 28 days before, during, and ≥ 28 days after completing lenalidomide

- HIV negative

- No uncontrolled infection requiring intravenous therapy or poorly controlled diabetes
mellitus

- No history of allergic reactions attributed to compounds of similar chemical or
biologic composition to lenalidomide

- No uncontrolled intercurrent illness including, but not limited to, any of the
following:

- Ongoing or active infection

- Symptomatic congestive heart failure

- Unstable angina pectoris

- Cardiac arrhythmia

- Psychiatric illness and/or social situations that would limit compliance with
study requirements

- No history of grade 3 or 4 graft-vs-host disease (GVHD)

- If patient has acute GVHD grade 1 or 2, GVHD must be controlled and dose of oral
prednisone or equivalent ≤ 20 mg per day (after AHSCT)

- More than 4 weeks since prior chemotherapy (excluding steroids), radiotherapy, or
radioimmunoconjugate therapy (6 weeks for nitrosoureas or mitomycin C) and recovered

- No other concurrent investigational agents