High frequency of germinal centre derivation in diffuse large B cell lymphoma from Asian patients

BACKGROUND Recent reports have divided diffuse large B cell lymphoma (DLBCL) into germinal centre B cell-like and activated B cell-like subgroups with implicated differences in prognosis. AIMS To delineate the germinal centre B cell derivation group from an Asian series of DLBCLs. METHODS Fifty four cases were analysed by polymerase chain reaction to detect the t(14;18) translocation and immunohistochemistry for BCL2, CD10, BCL6, and E2F1 expression. RESULTS Eighteen of 54 cases had bcl2 gene rearrangement, 36 of 52 expressed BCL2, 29 of 52 expressed BCL6, 20 of 53 expressed CD10, and 18 of 53 expressed E2F1. There was a significant association between bcl2 gene rearrangement and the expression of both BCL2 and CD10. Using the minimally acceptable criteria of t(14;18) rearrangement and/or CD10 expression, 26 of 54 cases were probably germinal centre derived, in agreement with other reports. A higher proportion of cases had t(14;18) translocation, suggesting that they may be derived from transformed follicular lymphomas. E2F1 positivity did not correlate with the known germinal centre markers, even though it has recently been suggested that it may be a new GC marker. CONCLUSIONS It may be possible to stratify patients for treatment using markers for specific lineages of B cell differentiation.