Inclusion Criteria

DISEASE CHARACTERISTICS:

- Diagnosis of leukemia or lymphoma with meningeal involvement defined as cerebrospinal
fluid cell count at least 5/mm^3 AND evidence of blast cells on cytospin preparation
or by cytology OR

- Diagnosis of other solid tumor with meningeal involvement defined as presence of
tumor cells on cytospin preparation or cytology OR presence of measurable meningeal
disease on CT or MRI scan

- Meningeal malignancy must be progressive or refractory to conventional therapy

- Meningeal malignancies secondary to an underlying solid tumor are allowed at
initial diagnosis provided there is no conventional therapy

- No concurrent bone marrow relapse in leukemia or lymphoma patients

- No clinical evidence of obstructive hydrocephalus or compartmentalization of the
cerebrospinal fluid flow as documented by a radioisotope indium In 111 or technetium
Te 99-DTPA flow study

- Patients demonstrating restored flow after focal radiotherapy are allowed

PATIENT CHARACTERISTICS:

Age:

- Over 3

Performance status:

- ECOG 0-2

Life expectancy:

- At least 8 weeks

Hematopoietic:

- Not specified

Hepatic:

- No clinically significant liver function abnormalities

Renal:

- No clinically significant renal function abnormalities

Other:

- Not pregnant or nursing

- Negative pregnancy test

- Fertile patients must use effective contraception during and for 6 months after study

- No clinically significant metabolic parameter abnormalities (e.g., electrolytes,
calcium, and phosphorus)

- No significant systemic illness (e.g., infection)

PRIOR CONCURRENT THERAPY:

Biologic therapy:

- Recovered from prior immunotherapy

Chemotherapy:

- At least 1 week since prior intrathecal chemotherapy (2 weeks for cytarabine
(liposomal)) and recovered

- Concurrent systemic chemotherapy to control systemic or bulk CNS disease allowed with
the following exceptions:

- No phase I agent

- No agent that significantly penetrates the CNS (e.g., high-dose systemic
methotrexate (more than 1 g/m^2), high-dose cytarabine (more than 2 g/m^2), IV
mercaptopurine, fluorouracil, topotecan, or thiotepa)

- No agent known to have serious unpredictable CNS side effects

Endocrine therapy:

- Not specified

Radiotherapy:

- See Disease Characteristics

- Recovered from prior radiotherapy

- At least 8 weeks since prior craniospinal irradiation

- Local radiotherapy for symptomatic or bulky CNS disease must be given prior to
induction therapy

- No concurrent whole brain or craniospinal irradiation

- Concurrent partial brain (e.g., base of brain) or limited-field spinal
radiotherapy for asymptomatic bulky (radiographically visible) CNS disease
allowed

- Total CNS radiotherapy dose must not exceed accepted safe tissue tolerances

Surgery:

- Not specified

Other:

- At least 1 week since any prior CNS therapy

- At least 7 days since prior intrathecal investigational agent

- At least 14 days since prior systemic investigational agent

- No other concurrent intrathecal or systemic investigational agent

- No other concurrent intrathecal or systemic therapy to treat meningeal malignancy

- No other concurrent intrathecal therapy or agent that significantly penetrates the
blood-brain barrier

- No concurrent agent known to have serious unpredictable CNS side effects