Influence of low absolute lymphocyte count of patients with nongerminal center type diffuse large B-cell lymphoma with R-CHOP therapy

Abstract

Background: Rituximab has dramatic impact on outcome of patients with diffuse large B-cell lymphoma (DLBCL), especially nongerminal center (non-GC) type. A low absolute lymphocyte count (ALC) before rituximab, cyclophosphamide, vincristine, adriamycin, and prednisone (R-CHOP) therapy as a surrogate marker of immune status is associated with poor clinical outcome in DLBCL. Therefore, we hypothesized that low ALC before R-CHOP would have effect on the survival in non-GC type. Patients and methods: One hundred and thirty-six DLBCL patients who were treated with R-CHOP from 2003 to 2007 were analyzed in the present study. Results: ALC ≥1.0 × 10⁹/l predicted a longer 3-year progression-free survival (PFS) and 3-year overall survival (OS) versus ALC 9/l (82.6% versus 60.0%, P = 0.005 and 87.2% versus 62.0%, P < 0.001, respectively). Non-GC type had similar PFS and OS to germinal center type (68.2% versus 80.0%, P = 0.074 and 72.7% versus 82.9%, P = 0.111, respectively). However, considering clinical influence of the ALC according to immunophenotype, low ALC in non-GC type DLBCL was associated with lower PFS and OS compared with others (PFS, P = 0.002; OS, P < 0.001). Multivariate analysis revealed that low ALC in non-GC type had lower PFS [hazard ratio (HR) = 3.324, P = 0.001] and OS (HR = 4.318, P < 0.001), independent of international prognostic index. Conclusion: A low ALC in non-GC type DLBCL counteracted the beneficial effect of rituximab on survival.