Objectives: B-cell activating factor of the tumor necrosis factor family (BAFF) and a proliferation-inducing ligand (APRIL) regulate survival and proliferation of B cells. Thus the association of elevated serum levels of BAFF and APRIL with worse prognosis has been suggested in B-cell lymphoid malignancies. However, the prognostic relevance of BAFF and APRIL is unknown in patients treated with rituximab, a monoclonal antibody targeting B-cell depletion.
Methods: We measured serum levels of BAFF and APRIL by enzyme-linked immunosorbent assay in 66 patients newly diagnosed as diffuse large B-cell lymphoma (DLBCL). All patients were treated with rituximab-CHOP chemotherapy.
Results: The mean (+/-standard deviation) serum level of BAFF (1 970.21 +/- 1 979.45 pg/mL) was higher in DLBCL than in controls (861.03 +/- 194.92 pg/mL, Mann-Whitney U-test, P < 0.001). When the patients were dichotomized into high and low BAFF group based on the median value (1 258.00 pg/mL), high BAFF group had less numbers of complete responders to rituximab-CHOP, and more relapses or progression after or during treatment. In multivariate analysis, serum BAFF was an independent prognostic factor for overall survival and progression-free survival (P < 0.05). Although serum levels of APRIL was also higher than controls (10.60 +/- 19.08 ng/mL vs. 1.10 +/- 0.30 ng/mL, P = 0.023), it failed to show prognostic significance.
Conclusions: Serum BAFF may be a useful indicator predicting prognosis in DLBCL patients treated with rituximab-containing chemotherapy.