title: Detection of ZAP-70 in patients with chronic lymphocytic leukemia.
abstract: OBJECTIVE
  To determine the presence and prognostic significance of ZAP-70 in patients with B chronic lymphocytic leukemia (B-CLL). Expression of ZAP-70 in B-CLL is a continuum ranging from absent to high, affecting the prognostic reliability of this marker.
  
  
  METHODS
  32 patients with B-CLL treated from March 2006 to February 2007 were prospectively studied. Patients were stratified in two groups: those diagnosed with B-CLL within 18 months and a retrospective group diagnosed before 18 months since the beginning of this study. Patients were predominantly males (78.1%), over 60 years old (81.25%). ZAP-70 was detected on EPICX-XL flow cytometer with System II software. Directly conjugated antibodies CD19 PE, ZAP-70 FITC (clone 1E7.2) and CD2 APC were used. Leuoperm was used for permeabilization. All samples with over 20% ZAP-70/CD19 double positive B lymphocytes were considered positive.
  
  
  RESULTS
  ZAP-70 was absent in a group of 22 patients with B-CLL diagnosed over 18 months from the beginning of this study, while 2 out of 10 (20%) patients from the group of newly diagnosed patients were ZAP-70(+). During follow up both ZAP-70(+) cases showed worsening of their clinical status resulting to death in one patient. In borderline cases with ZAP-70(+) ranging from 10.9-19.9% there was no correlation of the level of ZAP-70 expression with disease activity or clinical scoring systems.
  
  
  CONCLUSIONS
  Very high percentage of ZAP-70(+) cells is a sign of poor prognosis in B-CLL. Borderline expression of ZAP-70, although more frequent, could not be successfully assigned into a risk group.
authors.affiliation: Clinic of Hematology, Clinical Centre Nis, Serbia. prof.marjanovic@gmail.com
authors.forename: G
authors.initials: G
authors.lastname: Marjanovic
authors.forename: I
authors.initials: I
authors.lastname: Stanojevic
authors.forename: Lj
authors.initials: Lj
authors.lastname: Jankovic-Velickovic
authors.forename: W
authors.initials: W
authors.lastname: Hubl
authors.forename: V
authors.initials: V
authors.lastname: Marjanovic
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000097:blood* / Q000401:mortality; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D051746:ZAP-70 Protein-Tyrosine Kinase / Q000097:blood*
chemical_list: D051746:ZAP-70 Protein-Tyrosine Kinase