12 Pathology and Microbiology, and 13 Diffuse large B-cell lymphoma (DLBCL), the most common subtype of non-Hodgkin's lymphoma, is clinically heterogeneous: 40% of patients respond well to current therapy and have prolonged survival, whereas the remainder succumb to the disease. We proposed that this variability in natural history reflects unrecognized molecular heterogeneity in the tumours. Using DNA microarrays, we have conducted a systematic characterization of gene expression in B-cell malignancies. Here we show that there is diversity in gene expression among the tumours of DLBCL patients, apparently reflecting the variation in tumour proliferation rate, host response and differentiation state of the tumour. We identified two molecularly distinct forms of DLBCL which had gene expression patterns indicative of different stages of B-cell differentiation. One type expressed genes characteristic of germinal centre B cells ('germinal centre B-like DLBCL'); the second type expressed genes normally induced during in vitro activation of peripheral blood B cells ('activated B-like DLBCL'). Patients with germinal centre B-like DLBCL had a significantly better overall survival than those with activated B-like DLBCL. The molecular classification of tumours on the basis of gene expression can thus identify previously undetected and clinically significant subtypes of cancer.

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Distinct types of diffuse large B-cell lymphoma identified by gene expression profiling

Background The standard treatment for patients with diffuse large-B-cell lymphoma is cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP). Rituximab, a chimeric monoclonal antibody against the CD20 B-cell antigen, has therapeutic activity in diffuse large-B-cell lymphoma. We conducted a randomized trial to compare CHOP chemotherapy plus rituximab with CHOP alone in elderly patients with diffuse large-B-cell lymphoma. Methods Previously untreated patients with diffuse large-B-cell lymphoma, 60 to 80 years old, were randomly assigned to receive either eight cycles of CHOP every three weeks (197 patients) or eight cycles of CHOP plus rituximab given on day 1 of each cycle (202 patients). Results The rate of complete response was significantly higher in the group that received CHOP plus rituximab than in the group that received CHOP alone (76 percent vs. 63 percent, P=0.005). With a median follow-up of two years, event-free and overall survival times were significantly higher in the CHOP-plus-rit...

https://www.nejm.org/doi/pdf/10.1056/NEJMoa011795

CHOP Chemotherapy plus Rituximab Compared with CHOP Alone in Elderly Patients with Diffuse Large-B-Cell Lymphoma

https://www.nhlcyberfamily.org/tests/gene%20profiling%20diffuse.pdf

Confirmation of the molecular classification of diffuse large B-cell lymphoma by immunohistochemistry using a tissue microarray

The purpose of this work was to modernize recommendations for evaluation, staging, and response assessment of patients with Hodgkin lymphoma (HL) and non-Hodgkin lymphoma (NHL). A workshop was held at the 11th International Conference on Malignant Lymphoma in Lugano, Switzerland, in June 2011, that included leading hematologists, oncologists, radiation oncologists, pathologists, radiologists, and nuclear medicine physicians, representing major international lymphoma clinical trials groups and cancer centers. Clinical and imaging subcommittees presented their conclusions at a subsequent workshop at the 12th International Conference on Malignant Lymphoma, leading to revised criteria for staging and of the International Working Group Guidelines of 2007 for response. As a result, fluorodeoxyglucose (FDG) positron emission tomography (PET)–computed tomography (CT) was formally incorporated into standard staging for FDG-avid lymphomas. A modification of the Ann Arbor descriptive terminology will be used for ana...

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Recommendations for Initial Evaluation, Staging, and Response Assessment of Hodgkin and Non-Hodgkin Lymphoma: The Lugano Classification

Diffuse large B-cell lymphoma (DLBCL), the most common lymphoid malignancy in adults, is curable in less than 50% of patients. Prognostic models based on pre-treatment characteristics, such as the International Prognostic Index (IPI), are currently used to predict outcome in DLBCL. However, clinical outcome models identify neither the molecular basis of clinical heterogeneity, nor specific therapeutic targets. We analyzed the expression of 6,817 genes in diagnostic tumor specimens from DLBCL patients who received cyclophosphamide, adriamycin, vincristine and prednisone (CHOP)-based chemotherapy, and applied a supervised learning prediction method to identify cured versus fatal or refractory disease. The algorithm classified two categories of pa- tients with very different five-year overall survival rates (70% versus 12%). The model also ef- fectively delineated patients within specific IPI risk categories who were likely to be cured or to die of their disease. Genes implicated in DLBCL outcome included some that regulate responses to B-cell-receptor signaling, critical serine/threonine phosphorylation pathways and apoptosis. Our data indicate that supervised learning classification techniques can predict outcome in DLBCL and identify rational targets for intervention. © 2002 Nature Publishing Group http://medicine.nature.com

/pdf/diffuse-large-b-cell-lymphoma-outcome-prediction-by-gene-2dnd8dxnlx.pdf

Diffuse large B-cell lymphoma outcome prediction by gene-expression profiling and supervised machine learning

BACKGROUND\nAlthough many patients with intermediate-grade or high-grade (aggressive) non-Hodgkin's lymphoma are cured by combination chemotherapy, the remainder are not cured and ultimately die of their disease. The Ann Arbor classification, used to determine the stage of this disease, does not consistently distinguish between patients with different long-term prognoses. This project was undertaken to develop a model for predicting outcome in patients with aggressive non-Hodgkin's lymphoma on the basis of the patients' clinical characteristics before treatment.\n\n\nMETHODS\nAdults with aggressive non-Hodgkin's lymphoma from 16 institutions and cooperative groups in the United States, Europe, and Canada who were treated between 1982 and 1987 with combination-chemotherapy regimens containing doxorubicin were evaluated for clinical features predictive of overall survival and relapse-free survival. Features that remained independently significant in step-down regression analyses of survival were incorporated into models that identified groups of patients of all ages and groups of patients no more than 60 years old with different risks of death.\n\n\nRESULTS\nIn 2031 patients of all ages, our model, based on age, tumor stage, serum lactate dehydrogenase concentration, performance status, and number of extranodal disease sites, identified four risk groups with predicted five-year survival rates of 73 percent, 51 percent, 43 percent, and 26 percent. In 1274 patients 60 or younger, an age-adjusted model based on tumor stage, lactate dehydrogenase level, and performance status identified four risk groups with predicted five-year survival rates of 83 percent, 69 percent, 46 percent, and 32 percent. In both models, the increased risk of death was due to both a lower rate of complete responses and a higher rate of relapse from complete response. These two indexes, called the international index and the age-adjusted international index, were significantly more accurate than the Ann Arbor classification in predicting long-term survival.\n\n\nCONCLUSIONS\nThe international index and the age-adjusted international index should be used in the design of future therapeutic trials in patients with aggressive non-Hodgkin's lymphoma and in the selection of appropriate therapeutic approaches for individual patients.

D. Crowther

Papers

A predictive model for aggressive non-Hodgkin's lymphoma