This study is a retrospective analysis of an homogeneous population of patients with aggressive B-cell lymphoma and treated upfront with R-CHOP or R-CHOP like regimens to reassess the prognostic factors and hopefully to identify more accurate prognostic subgroups with a clinical and therapeutical relevance.

Inclusion Criteria:

1. Histologically confirmed newly diagnosed aggressive B-cell lymphoma according to the current World Health Organisation Classification, from 2001 to 2007.
2. Any stage of disease.
3. Treatment with R-CHOP or R-CHOP like regimens (+/- transplant).
4. Age at least 18 years.
5. Availability of tissue biopsy at diagnosis for a possible centralized revision.
6. Availability of data on clinical involvement, laboratory, treatment and follow up.

Exclusion Criteria:

• None

Cases of aggressive B-cell lymphoma diagnosed between 2001 to 2007 in Italy