Diffuse Large B-cell Lymphoma, Differential Diagnosis and Molecular Stratification

Abstract

Diffuse large B-cell lymphoma (DLBCL) is a clinically aggressive lymphoma. The diagnosis of DLBCL is based on morphological and immunophenotypical evaluation of the biopsy specimens. The pathologic diagnosis of DLBCL, while often straight forward, may be challenging from time to time, so much so that the most recent WHO classification of hematolymphoid neoplasms created two provisional categories dealing with the cases in which separation of DLBCL from other lymphomas can not be made with certainty. On the other hand, DLBCL is also a biologically and clinically heterogeneous entity. Treatment outcome in many cases has not been optimal. Research studies have provided new insight into the DLBCL and suggestions for further stratification of the disease to achieve better treatment outcomes. This review will highlight key differentiating points of the many different categories of lymphomas and non-lymphoid malignancies that need to be considered in the differential diagnosis of DLBCL. The current status of prognostic marker studies of DLBCL as an effort to further stratify DLBCL is also reviewed.