Pemetrexed Disodium in the Cerebrospinal Fluid of Patients With Leptomeningeal Metastases

DISEASE CHARACTERISTICS:

Diagnosis of systemic malignancy (solid tumor or hematologic malignancy) or primary CNS lymphoma with leptomeningeal metastases (LM) as documented by MRI, cerebrospinal fluid, or both
Patients may have brain metastases in addition to LM
Patients with clinically significant interstitial fluid with effusion controlled by drainage are eligible

PATIENT CHARACTERISTICS:

Karnofsky performance status 60-100%
Life expectancy > 2 months
Creatinine clearance ≥ 45 mL/min
Bilirubin < 1.5 times upper limit of normal (ULN)
Transaminases < 3.0 times ULN (5 times ULN for hepatic metastasis)
WBC > 3,000/mm³
Neutrophil count > 1,500/mm³
Platelet count > 100,000/mm³
Hemoglobin > 10 g/dL
Not pregnant or nursing
Negative pregnancy test
Fertile patients must use effective contraception during and for 3 months after completion of study treatment
Able to undergo lumbar puncture (i.e., no noncommunicating hydrocephalus or spinal block) or has an Ommaya reservoir in place
Able to take steroids, cyanocobalamin (vitamin B12), and folic acid
No other active cancer except nonmelanoma skin cancer or carcinoma in situ of the cervix
Patients with prior malignancies who are in complete remission and are off all therapy for that malignancy for ≥ 3 years are eligible
No significant medical or psychiatric illness that would interfere with study compliance

PRIOR CONCURRENT THERAPY:

More than 2 weeks since prior radiotherapy and recovered
No concurrent radiotherapy
No nonsteroidal anti-inflammatory drugs (NSAIDs) or acetylsalicylic acid within 2 days before or after study treatment (5 days for long-acting NSAIDs)
No other concurrent cytotoxic chemotherapy
Concurrent hormonal or biological therapy allowed