PKC-beta II expression has prognostic impact in nodal diffuse large B-cell lymphoma.

Abstract

Recent studies of gene expression and immunohistochemistry have shown that protein kinase C-beta II (PKC-beta II) might have prognostic significance in patients with diffuse large B-cell lymphoma (DLBCL). We sought to determine the prognostic significance of the expression of PKC-beta II in patients with nodal DLBCL. Formalin-fixed, paraffin-embedded tissues were stained with a monoclonal antibody to PKC-beta II protein. A total of 125 patients were studied; 83 patients (66%) were in the low-risk International Prognostic Index (IPI) group. Forty-eight patients (38%) were positive for PKC-beta II. Complete remission was obtained in 70%, and was not influenced by the PKC-beta II status (67 vs 71%). The 5-year event-free survival (EFS) was worse in high-risk patients (14 vs 58%, P<0.001) and in those with PKC-beta II positivity (36 vs 49%, P=0.054). In low-risk IPI patients, PKC-beta II expression was related to a worse 5-year overall survival (OS) (60 vs 76%, P=0.033) and a worse 5-year EFS (48 vs 66%, P=0.014). In a Cox regression analysis for EFS, both PKC-beta II expression (hazard ratio=1.68, P=0.037) and the IPI (HR=3.07, P<0.001) were independent poor prognostic factors. PKC-beta II (HR=1.72, P=0.046) and the IPI (HR=5.16, P<0.001) were also independent poor prognostic factors for the OS. PKC-beta II expression, along with the IPI, were associated with a worse EFS and OS in patients with nodal DLBCL specially in low-risk IPI patients.