• Overall response rate, including combined complete response and partial response [ Designated as safety issue: No ]
  

• Time to disease progression [ Designated as safety issue: No ]
  
• Time to next treatment [ Designated as safety issue: No ]
  
• Response duration in patients with responding disease [ Designated as safety issue: No ]
  
• Safety [ Designated as safety issue: Yes ]
  

OBJECTIVES:

Primary

• To evaluate the response rates in patients with relapsed follicular non-Hodgkin lymphoma treated with short-duration rituximab and combination chemotherapy (R-chemo) followed by rituximab and yttrium Y 90 ibritumomab tiuxetan.

Secondary

• To evaluate the duration of response in patients treated with this regimen.
• To evaluate the quality of response in order to determine the conversion rate from partial response to complete response in patients treated with this regimen.
• To evaluate the toxicity of yttrium Y 90 ibritumomab tiuxetan when administered after 3 courses of R-chemo.

OUTLINE: This is a multicenter study.

• Chemoimmunotherapy (R-CHOP or R-CVP): Patients receive R-CHOP comprising rituximab IV, cyclophosphamide IV, doxorubicin hydrochloride IV, and vincristine IV on day 1 and oral prednisolone on days 1-5. Alternatively, patients who have already been exposed to prior tolerance doses of anthracyclines receive R-CVP comprising rituximab IV, cyclophosphamide IV, and vincristine IV on day 1 and oral prednisolone on days 1-5. Treatment repeats every 3 weeks for up to 3 courses. Patients with objective evidence of response on CT scan or those with < 25% bone marrow involvement and no signs of bone marrow hypocellularity (< 15%) on bone marrow biopsy proceed to radioimmunotherapy.
• Radioimmunotherapy: Four to 6 weeks after completion of R-CHOP or R-CVP, patients receive rituximab IV followed no more than 4 hours later by yttrium Y 90 ibritumomab tiuxetan IV over 10 minutes. After completion of study therapy, patients are followed periodically for up to 5 years.