title: Adult T-cell leukaemia/lymphoma can mimic other lymphomas in a non-endemic area: dilemmas in diagnosis and treatment.
abstract: BACKGROUND
  The diagnosis of Adult T-cell leukaemia/lymphoma (ATL) in non-endemic regions is challenging.
  
  
  OBJECTIVE
  This study analyses the clinicopathologic features and diagnostic processes of ATL patients in Taiwan.
  
  
  METHODS
  ATL patients diagnosed and treated at Taipei Veterans General Hospital from 1998 through 2010 were retrospectively identified. The diagnosis of ATL was confirmed by in situ detection of human T-cell leukaemia virus type 1 (HTLV-1) when necessary. Patients' data were reviewed and analysed.
  
  
  RESULTS
  Fourteen ATL patients were identified, among whom six (42.9%) had an antecedent diagnosis of other malignant lymphomas before the ATL diagnosis, including two diagnosed with Hodgkin disease (HD), one with peripheral T-cell lymphoma, two with chronic lymphocytic leukaemia and one with angioimmunoblastic T-cell lymphoma. Of the 14 patients, eight (57%) were subclassified as the acute type, three (21.4%) as the lymphoma type, and three (21.4%) as the chronic type ATL. Five of six (83.3%) patients with initial non-ATL misdiagnosis were diagnosed with non-acute type ATL. In particular, a patient with an antecedent diagnosis of HD presented with typical Reed-Sternberg (RS)-like cells harbouring Epstein-Barr virus genomes in affected lymph nodes. The patient progressed to acute type ATL 3 years after the initial diagnosis, and HTLV-1 genomes were identified in the previous RS-like cells.
  
  
  CONCLUSIONS
  In non-endemic areas, such as Taiwan, ATL, particularly the non-acute type, may mimic other lymphomas and easily be misdiagnosed. HTLV-1 serology should be routinely screened in all malignant lymphoma patients. In situ detection of HTLV-1 is helpful in cases with diagnostic dilemmas.
authors.affiliation: Division of Haematology and Oncology, Taipei Veterans General Hospital, Taipei, Taiwan; Division of Haematology and Oncology, Department of Medicine, Yang-Ming Branch of Taipei City Hospital, Taipei, Taiwan; National Yang-Ming University School of Medicine, Taipei, Taiwan.
authors.forename: C-T
authors.initials: CT
authors.lastname: Huang
authors.forename: Y-H
authors.initials: YH
authors.lastname: Lee
authors.forename: K-C
authors.initials: KC
authors.lastname: Chow
authors.forename: C-F
authors.initials: CF
authors.lastname: Yang
authors.forename: P C-H
authors.initials: PC
authors.lastname: Chen
authors.forename: L-T
authors.initials: LT
authors.lastname: Hsiao
authors.forename: J-P
authors.initials: JP
authors.lastname: Gau
authors.forename: C-H
authors.initials: CH
authors.lastname: Tzeng
authors.forename: C-Y
authors.initials: CY
authors.lastname: Liu
authors.forename: T-J
authors.initials: TJ
authors.lastname: Chiou
mesh_terms: D000328:Adult; D003131:Combined Modality Therapy; D004279:DNA, Viral / Q000032:analysis*; D003937:Diagnosis, Differential; D019353:Endemic Diseases; D005260:Female; D005500:Follow-Up Studies; D015368:Human T-lymphotropic virus 1 / Q000235:genetics*; D006801:Humans; D017403:In Situ Hybridization; D015994:Incidence; D015459:Leukemia-Lymphoma, Adult T-Cell / Q000175:diagnosis* / Q000453:epidemiology / Q000628:therapy; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D012189:Retrospective Studies; D015996:Survival Rate / Q000639:trends; D013624:Taiwan / Q000453:epidemiology
chemical_list: D004279:DNA, Viral
keywords: Adult T-cell leukaemia/lymphoma; Hodgkin disease; Reed-Sternberg-like cell; human T-cell leukaemia virus type 1; in situ hybridisation