Clinicopathological observation of diffuse large B cell lymphoma and study of origin of its B cell

Aim:To observe the clinicopathological features,diagnosis and differential diagnosis of diffuse large B cell lymphoma(DLBCL)and the origin of its B cell.Methods:The clinicopathological materials were analysised,and expression of PAX-5,CD20,CD79a,CD3,CD43,CD45RO,CD15,CD30,CK,EMA,and ALK were detected by immunohistochemical SP technique in 63 cases with nodal and extra-nodal DLBCL.Meanwhile,expression of CD10,BCL-6,and MUM-1 were detected by same method in 24 cases with nodal DLBCL.Results:The diseased age of all patients was 52.9 years old.The location of the lesion included nodal and extranodal sites.Nodal DLBCL always involved the lymph nodes of cervix and upperclavicle,while extranodal DLBCL often involved gastroinstineal tract,tonsil,and oropharynx.Nodal enlarging,fever,and the organ-involved symptoms and signs were the major clinical manifestations of DLBCL.Histopathological variants presented as centroblastic variant(48 cases),immunoblastic variant(11 cases),anaplastic variant(3 cases),and T-cell/histocyte-rich variant(1 case).Tumor cell was positive for PAX-5,CD20,and CD79a in all 63 cases of DLBCL and positive for CD30 in all 3 cases of ALCL.The positive expression of CD10,BCL-6,and MUM-1 in 24 nodal DLBCL was account for 25.0%,45.8%,and 58.3%,respectively.24 cases nodal DLBCL were subdivided into germinal center B-cell-like(GCB,9 cases)and non-germinal center B-cell-like(non-GCB,15 cases).Conclusion:DLBCL is a group of heterogenous tumors.Further study of its clinical,histopathological immunophenotypical features,and the origin of its B cell through combination of CD10,BCL-6,MUM-1 have great significance to its diagnosis,differential diagnosis,and clinicoprognostic assessment.