• Molecular risk assessment to see how well it works in predicting response to therapy in patients who are receiving treatment for non-Hodgkin's lymphoma. [ Time Frame: Results from the genetic testing and PET scans at baseline and after course 3 to determine response. ] [ Designated as safety issue: No ]
  

Biological: rituximab
Rituximab IV over 3-6 hours.Treatment repeats every 21 days for 3-8 courses.
Drug: cyclophosphamide
Cyclophosphamide IV over 30 minutes. Treatment repeats every 21 days for 3-8 courses.
Drug: doxorubicin hydrochloride
Doxorubicin IV over 5 minutes. Treatment repeats every 21 days for 3-8 courses.
Drug: prednisone
Oral prednisone on days 1-5. Treatment repeats every 21 days for 3-8 courses.
Drug: vincristine sulfate
Vincristine IV over 5 minutes on day 1. Treatment repeats every 21 days for 3-8 courses.
Genetic: microarray analysis
genetic testing

OBJECTIVES:

• Determine whether molecular risk assessment can identify groups of patients with diffuse large B-cell non-Hodgkin's lymphoma (NHL) who will demonstrate at least 50% difference in early response rates to treatment as determined by positron-emission tomography (PET) imaging.
• Determine, by PET imaging, the response rate of patients treated with cyclophosphamide, doxorubicin, vincristine, prednisone, and rituximab.
• Determine whether early response rates can be predicted by gene expression profiles at diagnosis in these patients.
• Compare gene expression profiles of patients with refractory or relapsed large cell NHL with profiles of the disease at diagnosis.
• Determine relapse-free and overall survival rates of these patients.
• Determine the feasibility of a new NHL treatment algorithm based on prognostic index and molecular risk, and early response assessment by PET imaging.

OUTLINE: Molecular risk assessment is performed using lymph node tissue from initial diagnosis to test for "activated" genes before starting treatment.

Patients receive rituximab IV over 3-6 hours, cyclophosphamide IV over 30 minutes, doxorubicin IV over 5 minutes, and vincristine IV over 5 minutes on day 1 and oral prednisone on days 1-5. Treatment repeats every 21 days for 3-8 courses. Patients undergo whole-body positron-emission tomography (PET) scanning at baseline and after course 3 to determine response. Results from the genetic testing and PET scans are used to determine further treatment recommendations.

Patients are followed every 3 months for 1 year and then every 6 months for 2 years.

PROJECTED ACCRUAL: A total of 36-50 patients will be accrued for this study.