Rituximab, Ifosfamide, Carboplatin, and Etoposide (RICE) Followed by Gallium Nitrate, Rituximab and Dexamethasone (GARD) for Relapsed or Refractory Diffuse Large B-Cell Lymphoma

Inclusion Criteria: * Must have histologically or cytologically confirmed diffuse, large B-cell lymphoma (WHO classification diffuse large B-cell lymphoma or mediastinal large B-cell lymphoma), immunoblastic B cell lymphoma or Burkitts lymphoma. Transformed, large B-cell lymphoma will be excluded. * Must have measurable disease, defined as at least one lesion that can be accurately measured in at least one dimension (longest diameter to be recorded) as \>10 mm with spiral CT scan. * Must be refractory to initial therapy or have disease relapse from prior therapy and must be at least 3 weeks post treatment from prior chemotherapy or radiation therapy. * Age \>18 years. * Life expectancy \>24 weeks * SWOG performance status \<1 (Karnofsky \>80%). * Must have normal organ function (or impaired marrow function) as defined below: * leukocytes \> or equal to 1,500/mcL * absolute neutrophil count \>or equal to 1,000/mcL * platelets \>or equal to 50,000/mcL * total bilirubin within normal institutional limits * AST(SGOT)/ALT(SGPT)\<or equal to 2.5 X institutional upper limit of normal unless due to lymphoma involvement * creatinine clearance \> than or equal to 60 mL/min * Must agree not to become pregnant for the duration of study participation. * Ability to understand and the willingness to sign a written informed consent document. Exclusion Criteria: * Patients who have had chemotherapy or radiotherapy within 3 weeks (6 weeks for nitrosoureas or mitomycin C) prior to entering the study. * Follicular B-cell lymphomas, small lymphocytic lymphomas, chronic lymphocytic leukemia, lymphoblastic lymphomas and all T-cell lymphomas. * Patients may not be receiving any other investigational agents, within trials in the previous 4 weeks. * Patients with known CNS metastases are excluded from this clinical trial. * History of allergic reactions attributed to compounds of similar chemical or biologic composition to gallium nitrate, rituximab, dexamethasone, ifosfamide, carboplatin, and/or etoposide. * Prior therapy with gallium nitrate, ifosfamide, carboplatin and/or etoposide * Uncontrolled intercurrent illness including, but not limited to, ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social situations that would limit compliance with study requirements. * Pregnant and women who are nursing are excluded from this study. * Because patients with immune deficiency are at increased risk of lethal infections when treated with marrow-suppressive therapy, HIV-positive patients receiving combination anti-retroviral therapy are excluded from the study because of possible pharmacokinetic interactions with RICE and/or GaRD.