The present case illustrates a primary cutaneous mantle cell lymphoma of the leg, with blastoid morphology and aberrant expression of CD10 and bcl-6, which was misinterpreted at the beginning as diffuse large B-cell lymphoma.
Indeed, the lack of CD5 and expression of CD10 associated with MYC rearrangement detected on interphasic nuclei could support the diagnosis of diffuse large B-cell lymphoma or Burkitt lymphoma.
In 53 patients with diffuse large B-cell lymphoma and 20 patients with follicular lymphoma grade 3 with >75% follicular growth pattern the following was performed: 1) determination of protein expression of BCL6, CD10, MUM1/IRF4, CD138, and BCL2 by immunohistochemistry; 2) subclassification into germinal center B-cell-like (GCB) and activated B-cell-like (ABC) groups according to the results of protein expression; 3) detection of t(14;18)(q32;q21)/IgH-BCL2 and BCL6 abnormalities by fluorescent in situ hybridization in diffuse large B-cell lymphoma and follicular lymphoma grade 3 with >75% follicular growth pattern as well as in GCB and ABC groups; and 4) assessment of the influence of the analyzed characteristics and clinical prognostic factors on overall survival.
Samples of lymph nodes from 53 patients with newly diagnosed diffuse large B-cell lymphoma were taken at the time of the diagnosis and immunostained for CD10, MUM1, BCL6, BCL2, FOXP1, and FOXP3.
WILL1 is a useful tool to analyze the pathogenesis of CD5 and CD10 double-positive diffuse large B-cell lymphoma, and for molecular cloning of the unique translocation breakpoints of 14q32 and 8q24 and a novel gene on 6q27.
Regarding CD5+CD10+ diffuse large B-cell lymphoma with a non-random chromosomal translocation of t(6;14)(q15;q32), studies on the mechanism of lymphomagenesis are needed.
Immunohistochemical expression of CD10 and t(14;18) chromosomal translocation may be indicators of follicle centre cell origin in nodal diffuse large B-cell lymphoma.
These data suggest that the phenotypic delineation by the detection of CD5 and CD10 will improve our understanding of DLBL and be helpful in a future subgrouping of DLBL.