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