DISEASE CHARACTERISTICS:
* Histologically or cytologically confirmed renal cell carcinoma (RCC)
* Advanced or unresectable RCC
* Measurable disease, defined as at least one lesion that can be accurately measured in at least one dimension (longest diameter to be recorded) as ≥ 20 mm with conventional techniques OR ≥ 10 mm with spiral CT scan
* No brain metastases
* Brain metastases that have been treated with either radiotherapy or surgery and remain asymptomatic, with no active brain metastases, as shown by CT scan or MRI, for ≥ 6 months are allowed
PATIENT CHARACTERISTICS:
* ECOG performance status (PS) 0-1 OR Karnofsky PS 70-100%
* Absolute neutrophil count ≥ 1,500/mm³
* Platelet count ≥ 100,000/mm³
* Creatinine ≤ 2.0 mg/dL
* Bilirubin ≤ 1.5 mg/dL
* AST and ALT ≤ 2.5 times upper limit of normal (ULN) (5 times ULN if hepatic metastases are present)
* Not pregnant or nursing
* Negative pregnancy test
* Fertile patients must use effective contraception
* No other malignancies within the past 5 years, except for treated basal cell or squamous cell carcinoma of the skin, carcinoma in situ of the cervix or breast, localized prostate cancer, or superficial bladder cancer
* No history of allergic reactions attributed to compounds of similar chemical or biological composition to lenalidomide or thalidomide
* 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 or social situation that would limit study compliance
* No hepatitis A, B, or C positivity
* No HIV positivity
PRIOR CONCURRENT THERAPY:
* See Disease Characteristics
* No more than 1 prior systemic therapy for RCC (e.g., chemotherapy, hormonal therapy, immunotherapy)
* At least 4 weeks since prior surgery, radiotherapy, hormonal therapy, chemotherapy, or immunotherapy and recovered
* No prior lenalidomide
* No other concurrent anticancer agents or treatments
* No other concurrent investigational agents
* No concurrent sargramostim (GM-CSF), radiotherapy, or thalidomide
