title: Detection of telomerase activity in bronchial lavage as an adjunct to cytological diagnosis in lung cancer.
abstract: OBJECTIVE
  Definitive diagnosis of lung cancer with conventional methods may sometimes be difficult in clinical practice. Telomerase is a ribonucleoprotein DNA polymerase that maintains the telomeric region of chromosomes during successive rounds of cell division. Telomerase activity in body cavity fluids has been advocated to be a potential diagnostic marker for malignancy. We investigated the diagnostic value of telomerase activity in bronchial lavage samples of patients undergoing diagnosis of lung cancer.
  
  
  METHODS
  A total of 29 bronchial lavage samples were collected from patients in whom the diagnosis was confirmed with cytological and/or histological examinations. Patients were classified as lung cancer patients (Group 1, n = 22) and patients with benign disease (Group 2, n = 7). Telomerase activity was determined with polymerase chain reaction-based TRAP (The telomeric repeat amplification protocol) assay.
  
  
  RESULTS
  Cytological examination was diagnostic in 12 (54.5%) of 22 patients in Group 1, and in all seven patients of Group 2 (P = 0.063). Telomerase activity was positive in 16 (72.7%) of Group 1 patients, while it was positive in only 1 (14.3%) sample of a lung abscess in Group 2 (P = 0.011). The sensitivity rate of cytological examination when combined with telomerase activity (81.8%) was significantly greater than that of cytological examination alone (54.5%) (P = 0.031). The sensitivity and specificity of telomerase activity were 72.7 and 85.7%, respectively. Telomerase activity had a positive predictive value as 0.94 and negative predictive value as 0.50. Diagnostic accuracy of telomerase activity was 75.8%.
  
  
  CONCLUSIONS
  Telomerase activity in bronchial lavage is a highly sensitive diagnostic biomarker for malignancy and a potential complementary diagnostic technique to cytological examination in the diagnosis of lung cancer.
authors.affiliation: Department of Thoracic Surgery, Kirikkale University School of Medicine, 71100 Kirikkale, Turkey.
authors.forename: Erkan
authors.initials: E
authors.lastname: Dikmen
authors.forename: Murat
authors.initials: M
authors.lastname: Kara
authors.forename: Günnur
authors.initials: G
authors.lastname: Dikmen
authors.forename: Hüseyin
authors.initials: H
authors.lastname: Cakmak
authors.forename: Pakize
authors.initials: P
authors.lastname: Dogan
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis*; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry*; D018288:Carcinoma, Small Cell / Q000175:diagnosis*; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008169:Lung Abscess / Q000175:diagnosis; D008175:Lung Neoplasms / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction / Q000379:methods; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D019098:Telomerase / Q000032:analysis*
chemical_list: D014408:Biomarkers, Tumor; D019098:Telomerase