Case ReportsPeripheral T-cell Lymphoma With Progression to a Clonally Related, Epstein Barr Virus+, Cytotoxic Aggressive T-cell Lymphoma: Evidence for Secondary EBV Infection of an Established Malignant T-cell CloneLanger, Rupert MD*; Geissinger, Eva MD†; Rüdiger, Thomas MD†; von Schilling, Christoph MD‡; Ott, German MD† §; Mandl-Weber, Sonja PhD* ∥; Quintanilla-Martinez, Leticia MD¶ ♯; Fend, Falko MD* ¶ Author Information *Institute of Pathology ‡3rd Medical Department, Klinikum rechts der Isar, Technische Universität München ∥Department of Hematology and Oncology, Medizinische Klinik Innenstadt, Klinikum der Universität München ♯HGF Helmholtz Zentrum München, München, Germany †Institute of Pathology, Universität Würzburg, Würzburg §Institute of Clinical Pathology, Robert-Bosch-Krankenhaus, and Dr Margarete Fischer-Bosch Institute of Clinical Pharmacology, Stuttgart ¶Institute of Pathology, Universität Tübingen, Tübingen Correspondence: Rupert Langer, MD, Institute of Pathology, Klinikum Rechts der Isar, Technische Universität München, Trogerstrasse 18, D-81675 München, Germany (e-mail: [email protected]). The American Journal of Surgical Pathology: September 2010 - Volume 34 - Issue 9 - p 1382-1387 doi: 10.1097/PAS.0b013e3181ec577a Buy Metrics Abstract We report a case of primary Epstein Barr virus (EBV) negative peripheral T-cell lymphoma (PTCL) NOS in a 56-year-old female who-after an initially indolent course – simultaneously developed an aggressive, EBV+ cytotoxic large T-cell lymphoma, clonally related to the primary PTCL, and an EBV+, clonal large B-cell lymphoproliferation. The initial, EBV-negative PTCL had shown some features of angioimmunoblastic T-cell lymphoma and had responded well to steroid therapy. Two years later, rapidly fatal, progressive disease with multivisceral involvement developed. Histologically, extensive infiltrates of EBV+, CD8+ large cells were present, in addition to areas of the initial PTCL. Extensive comparative phenotypic and molecular analyses confirmed the presence of an identical CD8+ T-cell clone in the initial EBV-negative PTCL and the EBV+, CD8+ large cell lymphoma at the time of aggressive transformation. These results also justified the retrospective classification of PTCL, NOS for the initial lymphoma. This case shows that secondary EBV infection of an established malignant T-cell clone can occur and may contribute to aggressive transformation of PTCL. © 2010 Lippincott Williams & Wilkins, Inc.