Case ReportAn Enteropathy-like Indolent NK-Cell Proliferation Presenting in the Female Genital TractKrishnan, Rahul MD*; Ring, Kari MD*; Williams, Eli PhD†; Portell, Craig MD‡; Jaffe, Elaine S. MD§; Gru, Alejandro A. MD†Author Information Departments of *Obstetrics & Gynecology †Pathology ‡Hematology/Oncology, University of Virginia, Charlottesville, VA §Hematopathology Section, Laboratory of Pathology, National Institute of Health (NIH), Bethesda, MD Conflicts of Interest and Source of Funding: A.A.G. is a consultant and part of the advisory board for Seattle Genetics, Innate Pharma, and Stemline Therapeutics. The remaining have disclosed that they have no significant relationships with, or financial interest in, any commercial companies pertaining to this article. Correspondence: Alejandro A. Gru, MD, Department of Pathology & Dermatology, Division of Dermatopathology and Hematopathology, University of Virginia, 1215 Lee Street, Charlottesville, VA 22901 (e-mail: [email protected]). The American Journal of Surgical Pathology: April 2020 - Volume 44 - Issue 4 - p 561-565 doi: 10.1097/PAS.0000000000001387 Buy Metrics Abstract Natural killer (NK) cell enteropathy is a lymphoproliferative disorder, initially described by Mansoor and colleagues, that presents in the gastrointestinal tract, and is often mistaken for extranodal NK/T-cell lymphoma on first assessment. This population of cells in this process have an NK-cell phenotype (CD3, CD56, CD2, CD7), lacks evidence of Epstein-Barr virus infection, has germline rearrangement of the T-cell receptor, and a very indolent clinical course. Indeed, many of such patients had been originally diagnosed as having an NK/T-cell lymphoma, and subsequently received chemotherapy. We report a unique case where an indolent lymphoproliferative disorder with features that resemble NK-cell enteropathy is encountered for the first time outside the gastrointestinal tract, specifically in the female genitourinary tract. We provide morphologic, immunophenotypic, and molecular documentation of such, in association with a completely indolent clinical behavior of this type of process. Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.