Combination Chemotherapy and Rituximab in Treating Young Patients With Recurrent or Refractory Non-Hodgkin's Lymphoma or Acute Lymphoblastic Leukemia

Inclusion Criteria:

* Histologically confirmed B-cell non-Hodgkin's lymphoma OR acute lymphoblastic leukemia

  * CD20+ (confirmed by flow cytometry of tumor tissue, involved marrow, or CD20 immunostaining)
  * The following histologies are generally CD20+ and are eligible:

    * Diffuse large B-cell lymphoma, mediastinal (thymic) large B-cell lymphoma, or follicular lymphoma, grade III (rare), documented by flow cytometry or appropriate immunohistochemistry, any stage
    * Burkitt's lymphoma or atypical Burkitt's/Burkitt-like lymphoma, any stage
    * B-cell acute lymphoblastic leukemia, with FABL3 morphology and/or demonstration of surface immunoglobin by flow cytometry
    * Atypical precursor B-cell lymphoblastic lymphoma or other unusual histologies that are CD20+
* Measurable disease by clinical, radiographic, or histologic criteria
* Must be in first or later recurrence or have disease that is primarily refractory to conventional therapy
* No isolated CNS disease
* Performance status - ECOG 0-2
* At least 2 months
* Absolute neutrophil count ≥ 1,000/mm\^3\*
* Platelet count ≥ 100,000/mm\^3 (transfusion independent)\*
* Hemoglobin ≥ 10.0 g/dL (RBC transfusion allowed)\*
* Bilirubin ≤ 1.5 times normal
* ALT \< 2.5 times normal
* No chronic renal insufficiency

  * Renal insufficiency allowed provided it is secondary to tumor lysis syndrome
* Not pregnant or nursing
* Negative pregnancy test
* Fertile patients must use effective contraception during and for 3 months after study treatment
* HIV negative
* No active uncontrolled infection
* Seizure disorder allowed if well controlled with anticonvulsants
* No CNS toxicity greater than grade II
* At least 24 hours since prior growth factor(s)
* At least 60 days since prior biologic (antineoplastic) therapy
* Prior stem cell transplantation allowed provided the following criteria are met:

  * More than 60 days since transplantation
  * Hematopoietic lab value requirements are met (See Hematopoietic)
  * No evidence of graft-versus-host disease (if post-allogeneic transplantation)
* Prior monoclonal antibody therapy allowed (including rituximab)
* No other concurrent immunomodulating agents
* More than 2 weeks since prior myelosuppressive chemotherapy (4 weeks for nitrosoureas)
* No other concurrent chemotherapy
* No concurrent steroids (except for rituximab infusion-related symptoms)
* At least 2 weeks since prior local palliative radiotherapy (small port)
* At least 6 weeks since prior substantial bone marrow radiotherapy
* At least 6 months since prior craniospinal radiotherapy or radiotherapy to 50% or more of the pelvis
* Concurrent radiotherapy to localized painful, airway-compromising, or other acute organ-threatening lesions allowed provided at least 1 measurable lesion is not irradiated
* Recovered from prior therapy
* No concurrent participation in another phase II study