Multilobated B-cell lymphoma, a variant of centroblastic lymphoma. Report of four cases.

Four cases of multilobated B-cell lymphoma, one follicular and three diffuse, are described. Many of the lymphoma cells show marked lobulation of the nuclei, and possess multiple prominent nucleoli. There are admixed classical centrocytes, classical centroblasts, and cells with morphology intermediate between classical centroblasts and multilobated cells. Multilobated cells are also observed in small numbers in germinal centres of lymph nodes showing reactive follicular hyperplasia. We believe that the multilobated B-cell may represent one form of centroblast during transition between the centroblastic and centrocytic stages. Multilobated B-cell lymphoma may be its neoplastic counterpart in which the nuclear lobulation is further exaggerated.