B-cell lymphomas

The B-cell lymphomas (BCLs) represent 80% to 90% of non-Hodgkin lymphomas in the Western world and include multiple lymphoma subtypes with different biologies, natural histories, morphologic characteristics, immunophenotypes, genetic features, prognoses, and responses to therapy.1 Numerous subtypes of B-cell malignancies are defined according to the World Health Organization (WHO) classification (Table 32-1). Accurate subclassification of these BCLs has always been a challenge for pathologists, resulting in early application of new techniques in genetic analysis to these tumors to improve diagnostic accuracy. Today, the genetic features of BCLs are used not only to aid in rendering an accurate primary diagnosis, but also to predict prognosis, to assess for minimal residual disease after therapy, and even to help determine optimal therapy.