title: An improved flow cytometric assay for detection and discrimination between malignant cells and atypical mesothelial cells, in serous cavity effusions.
abstract: BACKGROUND
  The aim of this study was to evaluate a flow cytometric assay for the detection of malignant effusions.
  
  
  METHODS
  During the last 4-year period, 125 effusions suspicious for malignancy were prospectively analyzed by flow cytometry and conventional cytology. A three-step flow cytometric assay was performed, beginning with an initial informative panel of two protocols, containing SYTO-16, 7-AAD, CD71-PE, CD45-ECD, and CD66abce-FITC, CD64-PE, CD45-ECD, CD16-PECy5, CD14-PECy7, respectively. This was followed by a basic immunophenotypic panel of seven three-color combinations, containing in the first position, EMA, Ber-EP4, CD66abce, CD56, and intracellular desmin-33, combined with CD71-PE and CD45-PeCy5 in each tube. Finally, a cytokeratin-FITC/propidium iodide DNA panel was conducted, for the detection of aneuploidy in cytokeratin positive cells.
  
  
  RESULTS
  The sensitivity and specificity of flow cytometry were 85.1 and 97.8%, and of cytology 93.2 and 95.6%, respectively. A significant association was observed between the results of the two techniques (P < 0.001). Among eight atypical cases detected by cytology, five had been precisely characterized as malignant by flow cytometry. EMA and Ber-EP4 proved the most sensitive markers for malignancy diagnosis, while the detection of desmin-33 negative/cytokeratin positive cells had the simultaneous highest positive and negative predictive values. CD66abce was very specific, although nonsensitive, while DNA ploidy analysis was nonspecific, as hyperploidy was observed in reactive mesothelial cells.
  
  
  CONCLUSIONS
  A flow cytometric assay of high sensitivity and specificity is proposed for the routine identification of carcinoma cells in effusions and their distinction from atypical mesothelial cells, as an ancillary to conventional cytology.
authors.affiliation: Department of Immunology, Flow Cytometry Laboratory, Athens Regional General Hospital G. Gennimatas, 154 Messogion Avenue, Athens, Greece.
authors.forename: Nektaria A
authors.initials: NA
authors.lastname: Kentrou
authors.forename: Nikolaos J
authors.initials: NJ
authors.lastname: Tsagarakis
authors.forename: Konstantina
authors.initials: K
authors.lastname: Tzanetou
authors.forename: Maria
authors.initials: M
authors.lastname: Damala
authors.forename: Konstantinos A
authors.initials: KA
authors.lastname: Papadimitriou
authors.forename: Dimitra
authors.initials: D
authors.lastname: Skoumi
authors.forename: Aimilia
authors.initials: A
authors.lastname: Stratigaki
authors.forename: Nikolaos I
authors.initials: NI
authors.lastname: Anagnostopoulos
authors.forename: Eleni
authors.initials: E
authors.lastname: Malamou-Lada
authors.forename: Pauline
authors.initials: P
authors.lastname: Athanassiadou
authors.forename: George
authors.initials: G
authors.lastname: Paterakis
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000954:Antigens, Surface / Q000032:analysis / Q000276:immunology; D001202:Ascitic Fluid / Q000473:pathology*; D014408:Biomarkers, Tumor / Q000032:analysis / Q000276:immunology; D005260:Female; D005434:Flow Cytometry / Q000379:methods*; D006801:Humans; D016130:Immunophenotyping / Q000379:methods; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000175:diagnosis / Q000276:immunology; D010490:Pericardial Effusion / Q000473:pathology*; D010996:Pleural Effusion / Q000473:pathology*; D012680:Sensitivity and Specificity
chemical_list: D000954:Antigens, Surface; D014408:Biomarkers, Tumor