Immunoblastic lymphoma is one of 3 morphologic variants of diffuse large B cell lymphoma (DLBCL). The other 2 variants are centroblastic lymphoma and anaplastic B-cell lymphoma.
The disease is not recognized as a separate entity in the WHO classification (2008).

The postulated normal counterpart is a germinal centre B cell or an activated post germinal centre B cell.
The immunophenotype may help distinguishing germinal centre-derived DLBCL from activated B-cell derived DLBCL, the former being CD10+ (>30% of the cells), or BCL6+ and IRF4/MUM1-.
The immunophenotype reproduces that of DLBCL, with pan B-cell markers positive, surface and/or cytoplasmic Ig positive in the majority of the cases. The CD30 antigen is negative. CD5 is positive in 10% of the cases. CD10 is expressed in approximately half of the cases.

It accounts for approximately 1/4 of DLBCL.

The disease runs an aggressive course, as all DLBCL.

The lymph node section shows an overwhelming infiltrate (>90%) by medium-to-large size cells with centrally located nucleolus and fairly abundant basophilic cytoplasm.

Chemoimmunotherapy using anti CD20 monoclonal antibody rituximab in combination with CHOP or CHOP-like regimens is the standard of care.

Chemoimmunotherapy may cure 40-60% of the cases depending on age and risk factors.