Rituximab administration as part of initial therapy may be associated with a poorer outcome in young patients subsequently treated with stem cell transplantation for relapsed chemosensitive large B-cell lymphoma

Abstract

6665 Background: Treatment with rituximab in combination with CHOP chemotherapy (R-CHOP) has become standard as initial therapy for diffuse large B-cell lymphoma (DLBCL). Although concerns regarding increased resistance of DLBCL to further therapy after failing R-CHOP have been raised, recent data have suggested that the administration of rituximab prior to autologous stem cell transplantation (ASCT) does not affect the outcome of these patients. Methods: To corroborate these findings in a more uniformly treated patient population, we retrospectively analyzed 130 patients treated at a single institution between 1998 and 2003. Only patients with DLBCL initially treated with CHOP± R who subsequently relapsed were included. All patients received DHAP or ICE salvage chemotherapy without rituximab followed by ASCT. All patients received BEAM conditioning chemotherapy without rituximab and none received rituximab post transplantation. Results: Eighty-eight patients (67%) received CHOP as initial therapy and 42 (33%) received R-CHOP. The median age was 56 years (range 21–77), 83 patients were male and 47 were female. Based on the International Prognostic Index (IPI) at the time of ASCT, 66 patients were low risk, 48 low-intermediate and 16 high-intermediate risk. With a median follow up of 22 months, there was no difference in the time to progression (p=0.31) or overall survival (p=0.22) between patients initially treated with R-CHOP and those treated with CHOP. When patients >60 years (n=49) treated either with CHOP or R-CHOP were analyzed, there was no difference in overall survival (p=0.52). However, in patients ≤ 60 years (n=81) there was a significantly poorer survival (p=0.03) for those treated with R-CHOP when compared to those treated with CHOP. This finding remained significant in a multivariate analysis (p=0.03). Conclusions: Patients ≤60 years with DLBCL who receive R-CHOP as initial treatment may be less likely to be successfully treated with ASCT at the point of relapse when compared to those treated with CHOP alone. This finding should be confirmed in a larger multicenter patient cohort. No significant financial relationships to disclose.