Immunohistochemical profile and fluorescence in situ hybridization analysis of diffuse large B-cell lymphoma in Northern China

Context.-Gene expression profiling of diffuse large B-cell lymphoma using complementary DNA microarrays has revealed 2 major prognostic groups in Western countries: germinal center B-cell-like and nongerminal center B-cell-like lymphomas. Immunohistochemical analysis using antibodies specific for CD10, BCL6, and MUM1 has been proposed as a surrogate for gene expression profiling. Objective.-To study the immunohistochemical features of diffuse large B-cell lymphoma cases from northern China because geographic differences for this disease are known to exist. Design.-Morphologic, immunohistochemical, and fluorescence in situ hybridization analyses of 63 cases of diffuse large B-cell lymphoma from northern China. Results.-There were 38 men and 25 women with a median age of 57 years (range, 12-87 years). CD10 was positive in 19 cases (30%), BCL6 was positive in 22 cases (35%), and MUM1 was positive in 32 cases (51%). Twenty-one (33%) cases were germinal center B-cell-like lymphoma, and 42 (67%) were nongerminal center B-cell-like lymphoma. BCL2 was expressed more often in nongerminal center B-cell-like disease versus germinal center B-cell-like disease (60% versus 24%, P = .01) and in nodal versus extranodal (64% versus 30%, P = .01) cases. Fluorescence in situ hybridization analysis showed BCL6, MYC, and BCL2 rearrangements in 11 of 32 (34%), 8 of 27 (30%), and 11 of 50 (22%) cases, respectively. Conclusions.-These results add to what is known about the geographic variation of diffuse large B-cell lymphomas. In northern China, the frequency of the germinal center B-cell-like type and BCL6 expression and/or BCL6 rearrangement is less and the frequency of MYC rearrangement is greater than have been reported in Western countries.