Inclusion Criteria:

- Understand and voluntarily sign an informed consent form

- Able to adhere to the study visit schedule and other protocol requirements

- Multiple myeloma, having undergone an allogeneic stem cell transplant from a matched
or mismatched related or unrelated donor and have relapsed or have disease
progression

- Relapse is defined as reappearance of monoclonal protein in serum or urine by
immunofixation, new or increased bone lesions or hypercalcemia

- Disease progression is define as a 25% increase in monoclonal protein in serum or a
50% increase in 24 hour urinary monoclonal protein from the lowest level attained at
any time point after allogeneic transplant or new or increased bone lesions or
hypercalcemia

- All previous cancer therapy, including radiation, hormonal therapy and surgery, must
have been discontinued at least 4 weeks prior to treatment in this study, excluding
corticosteroids for GVHD

- Eastern Cooperative Oncology Group (ECOG) performance status of =< 2 at study entry

- Absolute neutrophil count >= 1.5 x 10^9/L

- Platelet count >= 50 x 10^9/L

- Serum creatinine =< 2.0 mg/dL

- Total bilirubin =< 1.5 mg/dL

- Aspartate aminotransferase (AST) (serum glutamic oxaloacetic transaminase [SGOT]) and
alanine aminotransferase (ALT) (serum glutamic pyruvic transaminase [SGPT]) =< 2 x
upper limit of normal (ULN) or =< 5 x ULN if hepatic metastases are present

- Females of childbearing potential (FCBP) must have a negative serum or urine
pregnancy test with a sensitivity of at least 50 mIU/mL within 24 hours of
prescribing lenalidomide (prescriptions must be filled within 7 days) 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

- Disease free of prior malignancies for >= 5 years with exception of currently treated
basal cell, squamous cell carcinoma of the skin, or carcinoma "in situ" of the cervix
or breast

- Able to take aspirin 81 or 325 mg daily as prophylactic anticoagulation (patients
intolerant to acetylsalicylic acid [ASA] may use Coumadin or low molecular weight
heparin)

- All study participants must be registered into the mandatory RevAssist program, and
be willing and able to comply with the requirements of RevAssist

Exclusion Criteria:

- Any serious medical condition, laboratory abnormality, or psychiatric illness that
would prevent the subject from signing the informed consent form

- Pregnant or breast feeding females; (lactating females must agree not to breast feed
while taking lenalidomide)

- Any condition, including the presence of laboratory abnormalities, which places the
subject at unacceptable risk if he/she were to participate in the study or confounds
the ability to interpret data from the study

- Use of any other experimental drug or therapy within 28 days of baseline

- Known hypersensitivity to thalidomide

- The development of erythema nodosum if characterized by a desquamating rash while
taking thalidomide or similar drugs

- Resistance to prior use of lenalidomide

- Concurrent use of other anti-cancer agents or treatments

- Known positive for human immunodeficiency virus (HIV) or infectious hepatitis, type
A, B or C

- Acute GVHD grades 3 or 4