Clinical analysis of 670 cases in two trials of the European Organization for the Research and Treatment of Cancer Lymphoma Cooperative Group subtyped according to the Revised European-American Classification of Lymphoid Neoplasms: a comparison with the Working Formulation

Abstract

In the Working Formulation (WF), non-Hodgkin's lymphomas (NHL) are grouped according t o their clinical behavior. These disorders are listed as entities defined by morphology, phenotype, and cytogenetics in the proposed Revised European-American Classification of Lymphoid Neoplasms (REAL), the clinical relevance of which is still debated. We analyzed 670 NHL cases included in two randomized clinical trials (EORTC 20855 WF-intermediatelhigh-grade and 20856 WF-low-grade malignancy) with histologic material available for review. Based on hematoxylin-eosin-stained sections, 77% of cases could be subtyped. lmmunophenotyping was considered t o be mandatory only in diagnosing T-cell lymphoma and anaplastic largecell lymphoma. Of 522 cases subtyped, 11% were mantle cell lymphoma (MCL), 5% were marginal zone B-cell lymphoma (MZBCL), 469'0 were follicle center lymphoma, and 32% were diffuse large B-cell HE TWO MAIN non-Hodgkin's lymphoma (NHL)T classifications currently in use in different parts of the world are the Working Formulation (WF) and the Kiel classification. The former was meant to be a translation system among different classifications' and the separation of histologic subgroups into low-, intermediate-, and high-grade categories was based on clinical experience. In contrast, the Kiel classification was based on the putative normal counterpart; grading was based on morphologic features and did not always correlate with clinical behavior? The WF and Kiel classifications have served as the basis for clinical trials on NHL over the last 10 years. Several entities, eg, chronic lymphocytic leukemia, hairy cell leukemia, lymphoblastic lymphoma, Burkitt's lymphoma, plasmacytoma, and mycosis fungoides, were never included in these clinical studies The publication costs of this article were defrayed in part by page charge payment. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. section 1734 solely to indicate this fact. 0 1996 by The American Society of Hematology. 0006-4971/96/871 O-OoO3$3.00/0 lymphoma. Statistical analysis and comparisons between classifications were made only within each trial and treatment group. MCL and MZBCL were characterized by a shorter median survival (3.4 and 4.1 years, respectively) in comparison with low-and intermediate-grade WF groups (>9.3 and 5.8 years, respectively). In terms of progressionfree survival, MCL showed a behavior similar t o the lowgrade group, with frequent relapses. Follicle center cell lymphomas behaved as low-grade lymphomas as defined by the WF and diffuse large B-cell lymphomas as the WFintermediate grade group. Because several NHL entities have a clinical behavior of their own, their recognition by the REAL classification offers clinicians additional information that is not obtained when the WF is used.

Monoclonal antibody NU‐B1 reacts with novel antigen on human B cells in mantle and marginal zones distinct from known CD molecules

“…Although NU-B1 did not react with recombinant CD79 protein, it reportedly had a pattern of cell surface reactivity identical to that of CD'iSb, when used to stain normal B cells and lymphoid tissues (2). We report here that h'U-Bl recognizes novel human B-cell-restricted molecules, and that previous and present studies support the idea that it could be useful 111 studying the immunophenotyping and classification of leukernidlymphoma and the pathogenesis of mantle cell lym phomas (20)(21)(22).…”

Clinicopathologic analysis of ocular adnexal lymphomas: Extranodal marginal zone b‐cell lymphoma constitutes the vast majority of ocular lymphomas among Koreans and affects younger patients

“…Previous studies suggest that the relative incidence of MALT-type lymphomas may vary among different populations [12][13][14][15][16]. In a National Institutes of Health (NIH)-sponsored epidemiologic study of 1,378 non-Hodgkin's lymphomas from eight different geographic areas in four continents using REAL classification, the relative incidences of MALT lymphoma varied from 3% in London to 13% in Lyon, although the differences were not statistically significant [12].…”

“…In a National Institutes of Health (NIH)-sponsored epidemiologic study of 1,378 non-Hodgkin's lymphomas from eight different geographic areas in four continents using REAL classification, the relative incidences of MALT lymphoma varied from 3% in London to 13% in Lyon, although the differences were not statistically significant [12]. MALT-type lymphoma is the second most common lymphoma subtype in Korea, comprising 16.7% of all non-Hodgkin's lymphomas [17], a significantly higher rate than the reported rates of 5% and 6% in European population by two large-scale studies [14,16,17]. In cases of gastric MALT lymphoma, a controlled study has shown a higher incidence of gastric MALT lymphoma in northeastern regions of Italy, where H. pylori infection is prevalent, when compared with a region of England with the low prevalence rate of H. pylori [13].…”

Feasibility of the TNM‐based staging system of ocular adnexal extranodal marginal zone lymphoma of mucosa‐associated lymphoid tissue (MALT lymphoma)

“…Several studies have shown that the relative incidence of ocular adnexal MALT lymphoma (OAML) varies among different populations [3]. The proportion of OAML among primary OALs is higher in Korea (86-98%) than in Western countries (50-78%) [4][5][6][7].…”