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BackgroundDiffuse large B-cell lymphoma is a clinically and molecularly heterogeneous disease. Gene expression profiling studies have shown that the tumor microenvironment affects survival and that the angiogenesis-related signature is prognostically unfavorable. The contribution of histopathological microvessel density to survival in diffuse large B-cell lymphomas treated with immunochemotherapy remains unknown. The purpose of this study is to assess the prognostic impact of histopathological microvessel density in two independent series of patients with diffuse large B-cell lymphoma treated with immunochemotherapy. Design and MethodsOne hundred and forty-seven patients from the Leukemia Lymphoma Molecular Profiling Project (training series) and 118 patients from the Catalan Lymphoma-Study group-GELCAB (validation cohort) were included in the study. Microvessels were immunostained with CD31 and quantified with a computerized image analysis system. The stromal scores previously defined in 110 Leukemia Lymphoma Molecular Profiling Project cases were used to analyze correlations with microvessel density data. ResultsMicrovessel density significantly correlated with the stromal score (r=0.3209; P<0.001). Patients with high microvessel density showed significantly poorer overall survival than those with low microvessel density both in the training series (4-year OS 54% vs. 78%; P=0.004) and in the validation cohort (57% vs. 81%; P=0.006). In multivariate analysis, in both groups high microvessel density was a statistically significant unfavorable prognostic factor independent of international prognostic index [training series: international prognostic index (relative risk 2.7; P=0.003); microvessel density (relative risk 1.96; P=0.002); validation cohort: international prognostic index (relative risk 4.74; P<0.001); microvessel density (relative risk 2.4; P=0.016)]. ConclusionsThese findings highlight the impact of angiogenesis in the outcome of patients with diffuse large B-cell lymphoma and the interest of evaluating antiangiogenic drugs in clinical trials.

Diffuse large B-cell lymphoma (DLBCL) prognostication requires additional biologic markers. miRNAs may constitute markers for cancer diagnosis, outcome, or therapy response. In the present study, we analyzed the miRNA expression profile in a retrospective multicenter series of 258 DLBCL patients uniformly treated with chemoimmunotherapy. Findings were correlated with overall survival (OS) and progression-free survival (PFS). miRNA and gene-expression profiles were studied using microarrays in an initial set of 36 cases. A selection of miRNAs associated with either DLBCL molecular subtypes (GCB/ABC) or clinical outcome were studied by multiplex RT-PCR in a test group of 240 cases with available formalinfixed, paraffin-embedded (FFPE) diagnostic samples. The samples were divided into a training set (123 patients) and used to derive miRNA-based and combined (with IPI score) Cox regression models in an independent validation series (117 patients). Our model based on miRNA expression predicts OS and PFS and improves upon the predictions based on clinical variables. Combined models with IPI score identified a high-risk group of patients with a 2-year OS and a PFS probability of < 50%. In summary, a precise miRNA signature is associated with poor clinical outcome in chemoimmunotherapy-treated DLBCL patients. This information improves upon IPI-based predictions and identifies a subgroup of candidate patients for alternative therapeutic regimens. (Blood. 2011; 118(4):1034-1040) IntroductionDiffuse large B-cell lymphoma (DLBCL) is the most common type of non-Hodgkin lymphoma in adults, accounting for Ͼ 80% of aggressive lymphomas. 1 DLBCL is a heterogeneous group of tumors with different genetic abnormalities, clinical features, responses to treatment, and prognosis. 2 This heterogeneity hinders outcome prediction based on clinical and/or molecular parameters.Combination therapy that associates CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) with rituximab (R-CHOP) has become a standard treatment for DLBCL, leading to complete remission rates of 75%-80% and a 3-to 5-year PFS of 50%-60%. [3][4][5][6][7][8] Nevertheless, patients who fail to respond to first-line therapy or relapse continue to pose a challenge, and identification at diagnosis of poor-outcome cases is crucial for deciding between alternative treatment schemes.The International Prognostic Index (IPI) has been the primary clinical tool for predicting the outcome of patients with aggressive non-Hodgkin lymphoma. 9 Original IPI factors were redistributed in patients treated with R-CHOP to give a revised score (R-IPI) that distinguishes 3 prognostic categories, with 4-year survival rates ranging from 94%-55% for poor-risk patients. 7 Nevertheless, the R-IPI does not discriminate patients with Ͻ 50% probability of survival, which restricts its clinical value. 7 The biologic heterogeneity of DLBCL has been shown substantially to reflect the cell origin of these tumors from germinal center or activated B cells. These differences are significant ind...