Predicting survival for diffuse large B‐cell lymphoma patients using baseline neutrophil/lymphocyte ratio

The neutrophil/lymphocyte (N/L) ratio at diagnosis has been shown to be a prognostic factor for survival in solid tumors. The N/L ratio at diagnosis as a prognostic factor for non-Hodgkin lymphoma (NHL) has not been studied. Thus, we studied N/L ratio at diagnosis as a prognostic factor for patients with diffuse large B-cell lymphoma (DLBCL) treated with R-CHOP. From 2000 until 2007, 255 consecutive DLBCL patients, originally diagnosed, treated with R-CHOP, and followed at Mayo Clinic, Rochester, were included in this study. With a median follow-up of 4.0 years (range: 0.3–9.0 years), patients with an N/L ratio 38°C; drenching sweats; and weight loss >10% of normal body weight), baseline N/L ratio, IPI index 16; Age ≥ 60, extranodal sites ≥2, LDH (abnormal versus normal levels), performance status ≥2, and stage (I/II versus III/IV), and postchemotherapy consolidation radiation. All patients received rituximab 375 mg m−2; cyclophosphamide 750 mg m−2; doxorubicin 50 mg m−2; vincristine 1.4 mg m−2; and prednisone 100 mg m−2 × 5 days, every 21 days. Response criteria were based on criteria from the Lymphoma International Workshop 24. Overall survival (OS) was defined as the time from diagnosis to death as a result of any causes or last follow-up. Progression-free survival (PFS) was defined as the time from diagnosis to disease progression, death as a result of any causes, or last follow-up. OS and PFS times were analyzed using the method described by Kaplan and Meier 25. Differences between survival curves were tested for statistical significance using the two-tailed log-rank test. The Cox proportional hazards model 26 was used to assess N/L ratio at diagnosis as a prognostic factor for OS and PFS times as well as to adjust for other known prognostic factors. The cutoff of N/L ratio ≥3.5 at diagnosis was supported by the data because it yielded the greatest differential in survival at N/L ratio ≥3.5 at diagnosis based on χ2 values analyzed at different cut-points between the 25th and 75th quartiles (2.4–6.3) from log-rank tests (χ2 = 15.6 for OS and χ2 = 18.7 for PFS). χ2-tests were used to determine relationships between categorical variables. The Wilcoxon/Kruskal-Wallis rank tests were used to determine associations between continuous variables and categories, and Spearman correlation coefficients were used to evaluate associations for continuous variables. Logistic regression models were also used to assess associations between prognostic variables. All P values represented were two-sided, and statistical significance was declared at P < 0.05. LFP had the original idea for the study, designed the study, analyzed and interpreted data, did statistical analysis, and wrote the manuscript. KR collected the data and wrote the manuscript. TH, DJI, INM, wrote the manuscript. SNM designed the study, analyzed and interpreted data, and wrote manuscript. Additional Supporting Information may be found in the online version of this article. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article. Luis F. Porrata*, Kay Ristow*, Thomas Habermann*, David J. Inwards*, Ivana N. Micallef*, Svetomir N. Markovic*, * Division of Hematology/Department of Medicine, Mayo College of Medicine, Rochester, Minnesota.