Inclusion Criteria

DISEASE CHARACTERISTICS: Primary central nervous system non-Hodgkin's lymphoma (PCNSL)
Clinically diagnosed intracranial space-occupying lesion Pathology consistent with
non-Hodgkin's lymphoma and reviewed by NCCTG Biopsy optional if characteristic history,
pathognomonic neuroimaging, and cytology are consistent with malignant lymphocytes from
vitrectomy, CSF, or both No occult systemic lymphoma or prior lymphoma No post-transplant
lymphoproliferative disorder Disease measurable or evaluable on postoperative
contrast-enhanced CT or MRI Postoperative therapy must start within 6 weeks of definitive
diagnosis

PATIENT CHARACTERISTICS: Age: 18 to 70 Performance status: ECOG 0-3 Hematopoietic: WBC at
least 4,000/mm3 Platelet count at least 120,000/mm3 Hepatic: Bilirubin no greater than 2
times normal AST no greater than 2 times normal Renal: Creatinine no greater than 1.5
times normal Cardiovascular: No heart failure No uncontrolled arrhythmia Pulmonary: No
severe pulmonary failure Other: No serious uncontrolled infection No active bleeding No
AIDS or HIV-positive serology No prior organ transplant No pregnant or nursing women
Negative pregnancy test required of fertile women Adequate contraception required of
fertile patients

PRIOR CONCURRENT THERAPY: Biologic therapy: Not specified Chemotherapy: No prior
chemotherapy Endocrine therapy: Corticosteroids allowed if dose fixed or decreasing for at
least 1 week prior to baseline scan Radiotherapy: No prior radiotherapy Surgery: Not
specified