title: Extranodal malignant lymphoma of the upperaerodigestive tract in King Chulalongkorn Memorial Hospital according to WHO classification.
abstract: BACKGROUND
  The Working Formulation commonly used to classify NHL in Thailand has been recognized as imperfect for primary extranodal lymphoma, especially in head and neck regions.
  
  
  OBJECTIVE
  To study the clinicopathological and immunohistochemical features of extranodal malignant lymphoma of the upper aerodigestive tract according to WHO classification.
  
  
  METHODS
  King Chulalongkorn Memorial Hospital.
  
  
  METHODS
  Descriptive study.
  
  
  METHODS
  77 Thai patients who presented between 1998 and 2003.
  
  
  METHODS
  Routine histology was performed and stained with H&E and immunohistochemistry, and clinical characteristics were recorded.
  
  
  RESULTS
  The patients included 42 males and 35 females, with an average age of 53.87 years. Tumor sites were as follows: Waldeyer ring (n = 42, 54.55%), sinonasal areas (n = 19, 24.67%), oral cavity (n = 9, 11.69%), hypopharynx (n = 4, 5.19%), and larynx (n = 3, 3.90%). Immunohistochemically, 57 tumors (74.02%) were of B-cell phenotype and 19 tumors (24.68%) were of T-cell phenotype. According to the WHO classification, 45 cases (58.43%) were large B-cell, 3 (3.90%) were Burkitt, 3 (3.90%) were marginal zone B-cell lymphomas of mucosa-associated lymphoid tissue (MALT), 4 (5.19%) were follicular lymphoma, 1 (1.30%) was precursor B-lymphoblastic lymphoma, and 1 (1.30%) were mantle cell lymphoma. Among the T-cell lymphomas, 9 (11.69%) were of peripheral T-cell lymphoma, unspecified, 9 (11.69%) were extranodal NK/T cell lymphoma, nasal type, and 1 (1.30%) were anaplastic large-cell lymphomas. In nasal cavity, 8 tumors (42.11%) were extranodal NK/T-cell lymphoma, nasal type, 5 (26.32%) were diffuse large B-cell lymphoma, 4 (21.05%) were peripheral T-cell lymphoma, unclassified, and 1 (5.26%) was Burkitt lymphoma.
  
  
  CONCLUSIONS
  Our data correspond with series from Japan, Hong Kong, and Korea, but there is a significant difference from Western population in T-cell lymphomas of sinonasal area especially extranodal NK/T cell lymphoma of nasal type and peripheral T-cell lymphoma, unspecified which had a higher frequency in Thailand, Japan, Hong Kong, and Korea.
authors.affiliation: Department of Pathology, Faculty of Medicine Chulalongkorn University, Bangkok 10330, Thailand. Thamathorn.A@chula.ac.th
authors.forename: Thamathorn
authors.initials: T
authors.lastname: Assanasen
authors.forename: Pongsak
authors.initials: P
authors.lastname: Wannakrairot
authors.forename: Somboon
authors.initials: S
authors.lastname: Keelawat
authors.forename: Nootchanat
authors.initials: N
authors.lastname: Pramprayoon
authors.forename: Mookda
authors.initials: M
authors.lastname: Chaipipat
mesh_terms: D004067:Digestive System Neoplasms / Q000145:classification / Q000175:diagnosis* / Q000473:pathology; D005260:Female; D006258:Head and Neck Neoplasms / Q000145:classification / Q000175:diagnosis* / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D008223:Lymphoma / Q000145:classification / Q000175:diagnosis* / Q000473:pathology; D008228:Lymphoma, Non-Hodgkin / Q000175:diagnosis / Q000473:pathology; D016399:Lymphoma, T-Cell / Q000175:diagnosis / Q000473:pathology; D008297:Male; D013785:Thailand