title: T-cell clonality assessment by next-generation sequencing improves detection sensitivity in mycosis fungoides.
abstract: BACKGROUND
  T-cell receptor (TCR) clonality assessment is a principal diagnostic test in the management of mycosis fungoides (MF). However, current polymerase chain reaction-based methods may produce ambiguous results, often because of low abundance of clonal T lymphocytes, resulting in weak clonal peaks that cannot be size-resolved by contemporary capillary electrophoresis (CE).
  
  
  OBJECTIVE
  We sought to determine if next-generation sequencing (NGS)-based detection has increased sensitivity for T-cell clonality over CE-based detection in MF.
  
  
  METHODS
  Clonality was determined by an NGS-based method in which the TCR-γ variable region was polymerase chain reaction amplified and the products sequenced to establish the identity of rearranged variable and joining regions.
  
  
  RESULTS
  Of the 35 MF cases tested, 29 (85%) showed a clonal T-cell rearrangement by NGS, compared with 15 (44%) by standard CE detection. Three patients with MF had follow-up testing that showed identical, clonal TCR sequences in subsequent skin biopsy specimens.
  
  
  CONCLUSIONS
  Clonal T-cell populations have been described in benign conditions; evidence of clonality alone, by any method, is not sufficient for diagnosis.
  
  
  CONCLUSIONS
  TCR clonality assessment by NGS has superior sensitivity compared with CE-based detection. Further, NGS enables tracking of specific clones across multiple time points for more accurate identification of recurrent MF.
authors.affiliation: Washington University School of Medicine, Saint Louis, Missouri.
authors.forename: Kari E
authors.initials: KE
authors.lastname: Sufficool
authors.affiliation: Washington University School of Medicine, Saint Louis, Missouri.
authors.forename: Christina M
authors.initials: CM
authors.lastname: Lockwood
authors.affiliation: Washington University School of Medicine, Saint Louis, Missouri.
authors.forename: Haley J
authors.initials: HJ
authors.lastname: Abel
authors.affiliation: Washington University School of Medicine, Saint Louis, Missouri.
authors.forename: Ian S
authors.initials: IS
authors.lastname: Hagemann
authors.affiliation: ARUP Laboratories, Salt Lake City, Utah.
authors.forename: Jonathan A
authors.initials: JA
authors.lastname: Schumacher
authors.affiliation: University of Utah School of Medicine, Salt Lake City, Utah.
authors.forename: Todd W
authors.initials: TW
authors.lastname: Kelley
authors.affiliation: Washington University School of Medicine, Saint Louis, Missouri. Electronic address: EDuncavage@path.wustl.edu.
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Duncavage
mesh_terms: D000328:Adult; D000368:Aged; D003001:Cloning, Molecular / Q000379:methods; D004273:DNA, Neoplasm / Q000235:genetics; D016208:Databases, Factual; D004586:Electrophoresis / Q000379:methods; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D009182:Mycosis Fungoides / Q000175:diagnosis* / Q000235:genetics*; D009364:Neoplasm Recurrence, Local / Q000235:genetics / Q000473:pathology; D016133:Polymerase Chain Reaction / Q000379:methods; D011379:Prognosis; D011948:Receptors, Antigen, T-Cell / Q000235:genetics*; D012189:Retrospective Studies; D012878:Skin Neoplasms / Q000175:diagnosis* / Q000235:genetics*
chemical_list: D004273:DNA, Neoplasm; D011948:Receptors, Antigen, T-Cell
keywords: T-cell clonality; T-cell receptor rearrangement; cutaneous T-cell lymphoma; molecular diagnostics; mycosis fungoides; next-generation sequencing