Diffuse large B-cell lymphoma: is morphologic subdivision useful in clinical management?

The diffuse large B-cell lymphoma category of the REAL classification encompasses different morphologic lymphoma subtypes in a single entity. The aim of this study is to determine the influence of the morphologic subdivision within this category with respect to clinical features and response to treatment. From January 1993 to October 1996, 132 patients were diagnosed de novo with diffuse large B-cell lymphoma in our institution. All cases were classified according to the REAL and the Updated Kiel classifications, and immunohistochemical study was performed in all of them. Sixty-three per cent of patients received chemotherapy with a curative approach. Of the 105 assessable patients, 80 cases (74%) were classified as centroblastic (CB) and 25 cases (26%) as immunoblastic (IB), according to the updated Kiel classification. These 2 subsets of lymphomas did not differ with respect to major clinical features and laboratory parameters. Both groups had a similar complete response rate with a uniform therapeutic approach and the overall 2-yr survival did not show statistical differences (49% in CB vs. 45% in IB). In conclusion, for clinicians, morphologic subdivision of the diffuse large B-cell lymphoma category into CB and IB subtypes has little clinical and prognostic significance.