IRTA1 is selectively expressed in nodal and extranodal marginal zone lymphomas

• Published in: Histopathology Vol. 61; no. 5; pp. 930 - 941
• Main Authors: Falini, Brunangelo, Agostinelli, Claudio, Bigerna, Barbara, Pucciarini, Alessandra, Pacini, Roberta, Tabarrini, Alessia, Falcinelli, Flavio, Piccioli, Milena, Paulli, Marco, Gambacorta, Marcello, Ponzoni, Maurilio, Tiacci, Enrico, Ascani, Stefano, Martelli, Maria Paola, Favera, Riccardo Dalla, Stein, Harald, Pileri, Stefano A
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.11.2012; Blackwell; Wiley Subscription Services, Inc
• Subjects: B-Lymphocytes - immunology; B-Lymphocytes - pathology; Biological and medical sciences; Biomarkers, Tumor - immunology; Biomarkers, Tumor - metabolism; Hematologic and hematopoietic diseases; Humans; Immunohistochemistry; In Situ Hybridization, Fluorescence; Investigative techniques, diagnostic techniques (general aspects); IRTA1; Leukemias. Malignant lymphomas. Malignant reticulosis. Myelofibrosis; Lymph Nodes - immunology; Lymph Nodes - pathology; Lymphoma, B-Cell - immunology; Lymphoma, B-Cell - pathology; Lymphoma, B-Cell, Marginal Zone - genetics; Lymphoma, B-Cell, Marginal Zone - immunology; Lymphoma, B-Cell, Marginal Zone - pathology; marginal zone lymphomas; Medical sciences; monoclonal antibodies; Pathology. Cytology. Biochemistry. Spectrometry. Miscellaneous investigative techniques; Receptors, Fc - metabolism; Spleen - immunology; Spleen - pathology; Translocation, Genetic; Immunohistochemistry; Lymph node; Marginal zone lymphoma; Malignant hemopathy; Monoclonal antibody; IRTA1; Extraganglionar; marginal zone lymphomas; Anatomic pathology; Chronic; Lymphoproliferative syndrome; Cancer; monoclonal antibodies
• ISSN: 0309-0167; 1365-2559; 1365-2559
• DOI: 10.1111/j.1365-2559.2012.04289.x

Falini B, Agostinelli C, Bigerna B, Pucciarini A, Pacini R, Tabarrini A, Falcinelli F, Piccioli M, Paulli M, Gambacorta M, Ponzoni M, Tiacci E, Ascani S, Martelli M P, Dalla Favera R, Stein H & Pileri S A 
(2012) Histopathology 61, 930–941 IRTA1 is selectively expressed in nodal and extranodal marginal zone lymphomas Aims:  The aim of this study was to search for a molecule selectively expressed by marginal zone (MZ) lymphomas (MZLs), whose diagnosis is currently based on morphological criteria and negativity for markers detectable in other B‐cell lymphomas. Methods and results:  Two thousand one hundred and four peripheral lymphomas of various types were immunostained with a monoclonal antibody against immunoglobulin superfamily receptor translocation‐associated 1 (IRTA1), which recognizes the equivalents of MZ in human lymphoid tissues other than spleen. IRTA1 expression was restricted to extranodal (93%) and nodal MZLs (73%) and to lymphomas with MZ differentiation. Extranodal MZL cells with the strongest IRTA1 expression were usually located adjacent to epithelia, mimicking the IRTA1 expression pattern of normal and acquired mucosa‐associated lymphoid tissue (MALT). The cytological features, growth pattern and IRTA1 positivity in nodal MZLs suggest they may derive from IRTA1+ perifollicular B cells or monocytoid B cells detectable in reactive lymph nodes. Double immunostaining for IRTA1/bcl‐6 tracked the colonization of B‐cell follicles by MZL cells, and showed modulation of their phenotype (e.g. acquisition of bcl‐6) during recirculation through germinal centres. MZL cells differentiating into plasma cells usually lost IRTA1. Conclusions:  These results further expand our knowledge of the biology of MZLs, and highlight IRTA1 as the first positive marker for MZLs, enabling more accurate diagnosis of these neoplasms.