Original Article Podoplanin (D2-40): A New Immunohistochemical Marker for Reactive Follicular Dendritic Cells and Follicular Dendritic Cell Sarcomas
Qingmei Xie, Lugen Chen, Kai Fu, Josephine Harter, Ken H. Young, Jaya Sunkara, Deborah Novak, Esperanza Villanueva-Siles and Howard Ratech
Department of Pathology, Creighton University Medical Center, Omaha, NE; Department of Pathology, Montefiore Medical Center/Albert Einstein College of Medicine, Bronx. NY; Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE; Department of Pathology and Laboratory Medicine, University of Wisconsin School of Medicine and Public Health, UW Paul P. Carbone Comprehensive Cancer Center, Madison, WI
Received 1 Aug 2007; accepted with revision 19 Aug 2007; available online 1 January 2008
Abstract: The diagnosis of follicular dendritic cell (FDC) sarcoma can be challenging because of its morphologic overlaps with many other spindle cell neoplasms and, therefore, new phenotypic markers will be helpful in its differential diagnosis. Podoplanin is a mucin-type transmembrane glycoprotein that has recently been detected in reactive FDCs. In this study, we investigated the expression patterns of podoplanin using a new mouse monoclonal antibody D2-40, and compared them with CD21, a well-established FDC marker, in a comprehensive panel of cases. The panel included 4 FDC sarcomas, 38 spindle cell neoplasms of other types, 25 reactive lymphoid hyperplasia, and 117 lymphoid and 5 myeloid malignant hematopoietic neoplasms. Our study revealed that D2-40 strongly stained 3 of 4 FDC sarcomas. In contrast, D2-40 stained only 2/38 other spindle cell neoplasms tested. Furthermore, we observed that D2-40 highlighted more FDC meshworks than CD21 in Castleman’s disease, follicular lymphoma, nodular lymphocyte predominance Hodgkin lymphoma, and residual reactive germinal centers in a variety of lymphoma types. D2-40 and CD21 stained an equal number of cases of reactive lymphoid hyperplasia, progressively transformed germinal centers and angioimmunoblastic T-cell lymphoma. No expression of podoplanin was detected in normal or neoplastic lymphoid and myeloid cells. We conclude that podoplanin (D2-40) is a sensitive and specific FDC marker, which is superior or equal to CD21 in evaluating both reactive and neoplastic FDCs. In addition, our results suggest that podoplanin (D2-40) can be used to support the diagnosis of FDC sarcoma. (IJCEP708002).
Address all correspondence to: Qingmei Xie, MD, Department of Pathology, Creighton University Medical Center, 601 N. 30th St., Omaha, NE 68131-2197, USA. Tel: 402-449-4630; Fax: 402-449-5252; Email: firstname.lastname@example.org