Yttrium Y 90 Ibritumomab Tiuxetan, Etoposide, Cyclophosphamide, and an AHSCT in Non-Hodgkin's Lymphoma Patients

DISEASE CHARACTERISTICS:

* Biopsy proven diagnosis of low- or intermediate-grade\* non-Hodgkin lymphoma (NHL) including any of the following:

  * Follicular small cleaved
  * Follicular mixed
  * Follicular large cell
  * Diffuse small cleaved
  * Diffuse mixed
  * Diffuse large cell
  * Immunoblastic (working formulation B, C, D, E, F, G and H) NOTE: \*A new classification scheme for adult non-Hodgkin lymphoma has been adopted by PDQ. The terminology of "indolent" or "aggressive" lymphoma will replace the former terminology of "low-", "intermediate-", or "high-" grade lymphoma. However, this protocol uses the former terminology.
* Mantle cell and transformed low-grade lymphomas allowed
* Demonstrated monoclonal CD20-positive B-cell population in lymph nodes and/or bone marrow
* Favorable biodistribution on imaging dose
* Patient either relapsed after achieving a complete (CR) or partial response (PR) to prior therapy, never responded to prior therapy, or has poor-risk disease

  * Sensitivity of disease based on 1 of the following:

    * Induction failure: patients who did not achieve a CR or PR from induction chemotherapy
    * Resistant relapse: patients who did not achieve a CR or PR from the most recent standard salvage chemotherapy
    * Sensitive relapse: patients who did achieve a CR or PR from the most recent standard salvage chemotherapy
  * Poor-risk disease defined as any of the following:

    * Age-adjusted International Prognostic Index (IPI) High- (3 risk factors) or High-Intermediate (2 risk factors) based on the following risk factors:

      * Stage III-IV disease
      * Elevated serum lactate dehydrogenase level
      * ECOG performance status 2-4
    * Patients with aggressive NHL including mantle cell lymphoma and who required 2 different induction chemotherapy regimens to achieve a CR/PR
    * Patients with B-cell NHL and who failed to achieve a CR after adequate induction chemotherapy regimen(s)
* Patients must have bone marrow aspiration and biopsy within 42 days before salvage chemotherapy or stem cell collection which show ≤ 10% lymphomatous involvement of total cellularity
* Normal cytogenetic study on bone marrow (prior to salvage chemotherapy or stem cell collection)

  * Cytogenetic study on peripheral blood is acceptable if bone marrow biopsy has already been done and shows no sign of myelodysplastic syndrome (MDS) or lymphoma and a repeat bone marrow is deemed unnecessary by attending physician
* No active or prior history of CNS diseases
* No human anti-mouse antibody (HAMA) or human anti-chimeric antibody

PATIENT CHARACTERISTICS:

* ECOG performance status (PS) 0-1 or Karnofsky PS 80-100%
* Platelet count normal
* Serum creatinine ≤ 1.5 mg/dL or creatinine clearance ≥ 60 mL/min
* FEV\_1 \> 65% of predicted or DLCO ≥ 50% of predicted
* LVEF \> 50% by ECHO or MUGA scan
* Bilirubin ≤ 1.5 times normal
* SGOT or SGPT ≤ 2 times normal
* HIV antibody-negative
* No prior malignancy except for adequately treated basal cell or squamous cell skin cancer, adequately treated noninvasive carcinoma, or other cancer from which the patient has been disease-free for at least five years
* No active evidence of hepatitis B or C infection
* No hepatitis B surface antigen positivity
* No history of alcohol abuse
* Body weight ≤ 250 pounds

PRIOR CONCURRENT THERAPY:

* See Disease Characteristics
* Patients who have received involved field external beam therapy to area excluding lung, heart, liver and kidney are allowed, but will be evaluated on a case-by-case basis
* Patients must have recovered from last therapy and should be at least four weeks from prior radiation or chemotherapy
* No prior radioimmunotherapy
* No prior bone marrow transplantation