title: Small-cell predominant extranodal NK/T cell lymphoma, nasal type: clinicopathological analysis of a series of cases diagnosed in a Western population.
abstract: OBJECTIVE
  Extranodal NK/T cell lymphoma, nasal type (ENKTCL) is usually composed of medium- to large-sized lymphoid cells showing prominent angiotrophism and tumour cell necrosis. We report 13 cases composed predominantly of small lymphocytes diagnosed in the United States and Western Europe.
  
  
  RESULTS
  Patients included seven females and six males aged 17-75 years. Ten presented with sinonasal and three with buccal disease. Nine had stage IE/IIE and four had stage IV disease. In five of seven patients with multiple biopsies at different time-intervals, the lymphoma was misinterpreted as representing chronic inflammation on an earlier biopsy. In all cases morphology showed a dense infiltrate of small lymphoid cells with minimal cytological atypia. Necrosis, angioinvasion and angiodestruction were each seen in 17%, 22% and 17% of biopsies. Median Ki67 was 5%. Four patients died of lymphoma 4-16 months after diagnosis, including three of four patients with stage IV disease; seven (54%) are alive with no evidence of disease at a median of 39 months; one patient with stage IV disease is alive at 10 months and one recurred at 17 months.
  
  
  CONCLUSIONS
  In sinonasal biopsies with predominantly small lymphocytic infiltrates with admixed chronic inflammation, focal hypercellularity, focal surface ulceration or microscopic bone invasion by small lymphoid cells should alert pathologists to the possibility of small-cell predominant ENKTCL. Awareness of the full histological spectrum of ENKTCL, particularly in non-endemic areas, is important in avoiding a delay in diagnosis and ensuring timely initiation of therapy.
authors.affiliation: The James Homer Wright Pathology Laboratories of the Massachusetts General Hospital and Department of Pathology, Harvard Medical School, Boston, MA, USA.|Department of Anatomical Pathology, St Vincent's Hospital, Melbourne, Australia.
authors.forename: Penelope A
authors.initials: PA
authors.lastname: McKelvie
authors.affiliation: Department of Pathology, University Hospital of Bellvitge-IDIBELL, Barcelona, Spain.
authors.forename: Fina
authors.initials: F
authors.lastname: Climent
authors.affiliation: Department of Pathology, University of California San Francisco School of Medicine, San Francisco, CA, USA.
authors.forename: Gregor
authors.initials: G
authors.lastname: Krings
authors.affiliation: The James Homer Wright Pathology Laboratories of the Massachusetts General Hospital and Department of Pathology, Harvard Medical School, Boston, MA, USA.
authors.forename: Robert P
authors.initials: RP
authors.lastname: Hasserjian
authors.affiliation: Center for Lymphoma, Massachusetts General Hospital Cancer Center and Department of Medicine, Harvard Medical School, Boston, MA, USA.
authors.forename: Jeremy S
authors.initials: JS
authors.lastname: Abramson
authors.affiliation: The James Homer Wright Pathology Laboratories of the Massachusetts General Hospital and Department of Pathology, Harvard Medical School, Boston, MA, USA.
authors.forename: Ben Z
authors.initials: BZ
authors.lastname: Pilch
authors.affiliation: The James Homer Wright Pathology Laboratories of the Massachusetts General Hospital and Department of Pathology, Harvard Medical School, Boston, MA, USA.
authors.forename: Nancy Lee
authors.initials: NL
authors.lastname: Harris
authors.affiliation: The James Homer Wright Pathology Laboratories of the Massachusetts General Hospital and Department of Pathology, Harvard Medical School, Boston, MA, USA.
authors.forename: Judith A
authors.initials: JA
authors.lastname: Ferry
authors.affiliation: The James Homer Wright Pathology Laboratories of the Massachusetts General Hospital and Department of Pathology, Harvard Medical School, Boston, MA, USA.
authors.forename: Lawrence R
authors.initials: LR
authors.lastname: Zukerberg
authors.affiliation: The James Homer Wright Pathology Laboratories of the Massachusetts General Hospital and Department of Pathology, Harvard Medical School, Boston, MA, USA. arsohani@mgh.harvard.edu.
authors.forename: Aliyah R
authors.initials: AR
authors.lastname: Sohani
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005060:Europe; D005260:Female; D006801:Humans; D054391:Lymphoma, Extranodal NK-T-Cell / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000473:pathology*; D010255:Paranasal Sinus Neoplasms / Q000473:pathology*; D014481:United States; D055815:Young Adult
keywords: EBERin-situ hybridization; Epstein-Barr virus; chronic active EBV infection; chronic rhinosinusitis; extranodal NK/T cell lymphoma; nasal type