e18533 Background: This study investigated the activation of nuclear factor kB (NFkB) and the chemokine receptor CXCR4 co-expression in patients with diffuse large B-cell lymphoma (DLBCL) who received rituximab-based therapy. Methods: Seventy patients with DLBCL and treated with rituximab-CHOP (RCHOP) were included. Tissue microarray blocks were created from 70 cases of DLBCL. Sections were stained with antibodies to IKKα, p-IkB, p50, p52, and CXCR4. To classify cases of DLBCL into GCB (germinal center B-cell-like) and non-GCB, additional immunohistochemical expression of CD10, bcl-6, or MUM1 has been used in this study. A numeric intensity score of 0-3 was assigned each case. Negative was scored if 0/+1 and positive was scored if 2+/3+. Results: The median age was 66.5 years (range, 17-87) and 58.6% were male. Twenty-seven patients (38.6%) had stage III and IV at diagnosis. Twenty-three patients (32.9%) were categorized as high or high-intermediate risk according to their IPI. The overall incidence of BM involvement was 5.7%. Positive expression for NFkB and CXCR4 were more than 80%. In NFkB and CXCR4 status, there are no significant difference between GCB and non-GCB. High NFkB expression is associated with CXCR4 expression and they are co-expressed in about two thirds of patients. With a median follow-up duration of 28.7 months (range, 0.1-76.1), the 5-year overall survival (OS) and event-free survival (EFS) rate was 67.4% and 79.8%, respectively. Neither NFkB nor CXCR4 were associated with DLBCL outcomes. Conclusions: In concolusion, none of the NFkB and CXCR4 expression profiles investigated in this study was found to be an independent prognostic marker for Korean patients with DLBCL. However, further studies on a larger scale are warranted to clarify the role of NFkB and CXCR4 as a prognostic marker.
High CXCR4 expression impairs rituximab response and the prognosis of R-CHOP-treated diffuse large B-cell lymphoma patients