Original ArticlesPrimary Cutaneous NK/T-cell Lymphoma, Nasal Type and CD56-positive Peripheral T-cell Lymphoma A Cellular Lineage and Clinicopathologic Study of 60 Patients From AsiaTakata, Katsuyoshi MD, PhD*; Hong, Min-eui MD†; Sitthinamsuwan, Panitta MD‡; Loong, Florence MD§; Tan, Soo-Yong MD, PhD∥; Liau, Jau-Yu MD¶; Hsieh, Pin-Pen MD#; Ng, Siok-Bian MD**,††; Yang, Sheau-Fang MD‡‡; Pongpruttipan, Tawatchai MD‡; Sukpanichnant, Sanya MD‡; Kwong, Yok-Lam MD§§; Hyeh Ko, Young MD, PhD∥∥; Cho, Yung-Tsu MD¶¶; Chng, Wee Joo MB, ChB, PhD††,##; Matsushita, Takashi MD, PhD***; Yoshino, Tadashi MD, PhD*; Chuang, Shih-Sung MD†††Author Information *Department of Pathology, Okayama University Graduate School of Medicine Medical School, Okayama ***Department of Dermatology, Faculty of Medicine, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Japan †Department of Pathology, Samsung Medical Center ∥∥Department of Pathology, Samsung Medical Center and Sungkyunkwan University, Seoul, Korea ‡Department of Pathology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand Departments of §Pathology §§Medicine, Queen Mary Hospital, Hong Kong SAR, China ∥Department of Pathology, Singapore General Hospital Departments of **Pathology ##Haematology-Oncology, National University Health System ††Cancer Science Institute of Singapore, National University of Singapore, Singapore ¶Department of Pathology, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan †††Department of Pathology, Chi-Mei Medical Center, Tainan, Taipei Medical University and National Taiwan University ¶¶Department of Dermatology, National Taiwan University Hospital, Taipei #Department of Pathology and Laboratory Medicine, Kaohsiung Veterans General Hospital ‡‡Department of Pathology, Kaohsiung Medical University Hospital and College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan Supplemental Digital Content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal's Website, www.ajsp.com. Part of this work had been presented at the 5th Asian Hematopathology Symposium on January 26th, 2014 in Nagoya, Japan and at the annual meeting of the United States and Canadian Academy of Pathology, March 1-7, 2014 in San Diego, CA Conflicts of Interest and Source of Funding: Supported by grants NSC101-2314-B-384-006 and NSC102-2320-B-384-001 from National Science Council, Taipei, Taiwan. The authors have disclosed that they have no significant relationships with, or financial interest in, any commercial companies pertaining to this article. Correspondence: Shih-Sung Chuang, MD, Department of Pathology, Chi-Mei Medical Center, 901 Chung-hwa Road, Yong-Kang District, 71004 Tainan, Taiwan (e-mail: [email protected]). The American Journal of Surgical Pathology: January 2015 - Volume 39 - Issue 1 - p 1-12 doi: 10.1097/PAS.0000000000000312 Buy SDC Metrics Abstract Primary cutaneous, extranodal natural killer/T-cell lymphoma, nasal type (PC-ENKTL), is a rare Epstein-Barr virus (EBV)-associated neoplasm with poorly defined clinicopathologic features. We performed a multinational retrospective study of PC-ENKTL and CD56-positive EBV-negative peripheral T-cell lymphoma (PC-CD56+PTCL) in Asia in an attempt to elucidate their clinicopathologic features. Using immunohistochemistry for T-cell receptors (TCRs), in situ hybridization for EBV, and TCR gene rearrangement, we classified 60 tumors into 51 with PC-ENKTL (20 of NK-cell, 17 T-cell, and 14 indeterminate lineages) and 9 with PC-CD56+PTCL. Tumors of T-cell origin accounted for 46% of PC-ENKTLs with half of these cases being TCR-silent. As compared with T-lineage tumors, PC-ENKTLs of NK-cell lineage had more frequent involvement of regional lymph nodes and more frequently CD8-negative and CD56-positive. Cases of PC-ENKTL showed more frequent tumor necrosis, younger age, and a higher frequency of CD16 and CD30 expression than cases of PC-CD56+PTCL. CD56-positive T-lineage PC-ENKTL tumors (n=8) had more localized disease in the TNM (tumor-node-metastasis) staging and were more often of γδ T-cell origin compared with cases of PC-CD56+PTCL (n=9). PC-ENKTLs and PC-CD56+PTCLs were equally aggressive, with a 5-year overall survival rate of 25%. Tumor necrosis and CD16 expression may serve as useful surrogates for differentiating PC-ENKTL from PC-CD56+PTCL. A single lesion, an elevated lactate dehydrogenase level, and the presence of B symptoms were independent poor prognostic factors for PC-ENKTL in multivariate analysis. Further studies with more cases are warranted to delineate the clinicopathologic features and significance of EBV in these rare lymphomas. © 2015 by Lippincott Williams & Wilkins.