[Classification and differential diagnosis of B-cell lymphomas]

The standard for the pathological identification of B-cell lymphomas is the World Health Organization (WHO) classification, which integrates tumor morphology, immunophenotype, recurrent genetic abnormalities and clinical features. The lymphoma entities defined in this classification are derived from virtually every stage of normal B-cell differentiation. This classification which has gained wide acceptance has proven useful in patient management and treatment. Novel findings based on gene expression profiling have however started to reveal that not all described entities are entirely molecularly homogeneous. This report describes distinct examples of the more common B-cell lymphomas along with the pathogenetic models and gives some information on the novel gene expression profiling data.