Joseph M. Connors

Between April 1981 and May 1984, 61 patients with advanced diffuse large-cell lymphoma completed treatment with MACOP-B (methotrexate with leucovorin rescue, doxorubicin, cyclophosphamide, vincristine, prednisone, and bleomycin), an innovative pilot chemotherapy program emphasizing weekly treatment, antibiotic prophylaxis, daily corticosteroid treatments, and brief duration (12 weeks). Fifty-one patients (84%) achieved a complete response and 10 patients (16%) had a partial response. Over a median follow-up after treatment of 23 months, the actuarial overall survival for the entire group has been 76%; for complete responders the relapse-free survival has been 90%. Toxicity was modest with one treatment-related death and seven episodes of serious infection. The most frequent toxicity was mucositis. Thus, MACOP-B is an effective treatment for large-cell lymphoma that can be delivered in 12 weeks with an acceptable incidence of toxicity. This regimen can achieve results similar and possibly superior to those of other presently used regimens of longer duration.

BACKGROUND: Diffuse 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 METHODS: One 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. RESULTS: Microvessel 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)]. CONCLUSIONS: These 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.

BACKGROUND: BCL6 gene rearrangement is the most frequent chromosomal abnormality in diffuse large B-cell lymphoma, a malignancy characterized by genetic heterogeneity and wide variability in clinical outcome. The prognostic significance of BCL6 rearrangement has not been evaluated in the context of rituximab therapy for diffuse large B-cell lymphoma. We analyzed the effect of the BCL6 rearrangement on survival in patients with diffuse large B-cell lymphoma treated with CHOP and CHOP plus rituximab (R-CHOP). DESIGN AND METHODS: BCL6 rearrangement status was analyzed by fluorescence in situ hybridization with break-apart probes in 164 patients with diffuse large B-cell lymphoma treated with CHOP (n=65) or R-CHOP (n=99). Cell-of-origin immunophenotype including BCL6 protein expression were determined by immunohistochemistry on a tissue microarray. RESULTS: BCL6 rearrangement was detected in 19.5% of cases. The presence of the gene rearrangement was associated with a non-germinal center B-cell immunophenotype (P=0.006), and showed no correlation with BCL6 protein expression. A trend toward inferior overall survival was observed in association with the BCL6 rearrangement among patients treated with R-CHOP (P=0.08), but not among patients treated with CHOP (P=0.64). However, BCL6 rearrangement also correlated with a high International Prognostic Index score (P=0.02), and did not demonstrate independent prognostic value by multivariate analysis. CONCLUSIONS: The introduction of rituximab may have altered the prognostic impact of BCL6 gene rearrangement in patients with diffuse large B-cell lymphoma. However, prospective analysis within large randomized clinical trials will be needed to clarify the prognostic significance of this biomarker in the rituximab era.