title: Multiparameter flow cytometry in the differential diagnosis of aberrant T-cell clones of unclear significance.
abstract: Immunophenotypic distinction between neoplastic and reactive T-cell clones can be challenging, as peripheral T-cell lymphomas (PTCLs) lack an immunophenotypic marker of clonality. Systematic screening of 10,510 cases analyzed by immunophenotyping at our institution between 2006 and 2012 resulted in 49 cases with aberrant T-cell populations of unclear significance. Review of patient charts allowed us to assign these cases to three categories. In 21 cases, PTCL could later be confirmed by complementary diagnostics (PTCL group). In 20 cases, follow-up confirmed the reactive nature of the aberrant T-cells (non-PTCL group). Eight cases remained of unclear significance. Neither the population size nor the number of aberrant markers differed significantly between the PTCL and non-PTCL groups. Only loss of CD7 was found significantly more often in patients with PTCL than in patients with non-PTCL (p = 0.037). Our data show that aberrant T-cell populations need to be interpreted in the clinicopathological context, as reactive and neoplastic phenotypes largely overlap.
authors.affiliation: Department of Oncology, Hematology and Bone Marrow Transplantation with Section Pneumology, Hubertus Wald Tumorzentrum (University Comprehensive Cancer Center Hamburg), University Medical Center Hamburg-Eppendorf , Hamburg , Germany.
authors.forename: Anna
authors.initials: A
authors.lastname: Flammiger
authors.forename: Ulrike
authors.initials: U
authors.lastname: Bacher
authors.forename: Maximilian
authors.initials: M
authors.lastname: Christopeit
authors.forename: Christiane
authors.initials: C
authors.lastname: Horn
authors.forename: Elke
authors.initials: E
authors.lastname: Rühlmann
authors.forename: Katrin
authors.initials: K
authors.lastname: Kluge
authors.forename: Eik
authors.initials: E
authors.lastname: Vettorazzi
authors.forename: Carsten
authors.initials: C
authors.lastname: Bokemeyer
authors.forename: Mascha
authors.initials: M
authors.lastname: Binder
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019011:Antigens, CD7 / Q000378:metabolism; D002999:Clone Cells / Q000473:pathology*; D005260:Female; D005434:Flow Cytometry / Q000379:methods*; D006801:Humans; D016130:Immunophenotyping / Q000379:methods; D016411:Lymphoma, T-Cell, Peripheral / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D013601:T-Lymphocytes / Q000473:pathology*; D055815:Young Adult
chemical_list: D019011:Antigens, CD7
keywords: Multiparameter flow cytometry; immunophenotyping; peripheral T-cell lymphoma; reactive T-cells