Combination Chemotherapy With or Without Autologous Stem Cell Transplant in Treating Patients With Central Nervous System B-Cell Lymphoma

1. Documentation of Disease: Diagnosis of primary CNS diffuse large B-cell lymphoma confirmed by one of the following: brain biopsy or resection, cerebrospinal fluid and vitreous fluid.
2. Other Lymphomas: Patients must have no evidence or history of non-Hodgkin lymphoma (NHL) outside of CNS.
3. Previous Treatment: Patients must have no prior chemotherapy or radiation therapy for lymphoma.
4. Age- Patients must be between the ages of 18 and 75 years.
5. Karnofsky Performance Scale - Patients must measure Karnofsky Performance Scale ≥ 30 (≥ 50 for patients ages 60-70).
6. Pregnancy and Nursing Status - Patients must be non-pregnant and non-nursing; women of childbearing potential must have a negative serum or urine pregnancy test 10-14 days prior to registration; in addition, women and men of childbearing potential must commit to use an effective form of contraception throughout their participation in this study; appropriate methods of birth control include abstinence, oral contraceptives, implantable hormonal contraceptives, or double barrier method (diaphragm plus condom)
7. HIV - Patients must have negative HIV serology.
8. Hepatitis - Patients must have negative HCV serology (unless HBsAb positive patient has recently received HBV vaccine, in this case HBcAb should be negative). All patients must be screened for hepatitis B infection before starting treatment. Those patients who test positive for hepatitis B should be closely monitored for evidence of active HBV infection and hepatitis during and for several months after rituximab treatment. PCNSL patients with a history of hepatitis B infection should be treated with entecavir or lamivudine (physician discretion for choice of drug) as antiviral prophylaxis to prevent hepatitis B reactivation.
9. Organ Transplant or Immunosuppressant Therapy - Patient must have no history of organ transplantation or ongoing immunosuppressant therapy.
10. Required Initial Laboratory Values: ANC ≥ 1500/mcL, AST and ALT \< 2 x upper limit of normal (ULN), total bilirubin ≤ 3 mg/dL, creatinine clearance ≥ 50 mL/min, platelet count ≥ 100,000/mcL