title: [Analysis of tumour-derived DNA in serum in advanced non-microcytic lung cancer: might it be a prognostic factor?].
abstract: BACKGROUND
  Presence of circulating DNA in the serum of patients with cancer makes detection of tumour-specific genetic alterations feasible.
  
  
  OBJECTIVE
  To study serum DNA concentration in patients diagnosed as having advanced Non-Small Cell Lung Cancer (NSCLC) and to evaluate its relationship with age, histology, stage, response, time-to-progression (TTP), and survival.
  
  
  METHODS
  Serum DNA from 78 patients was purified and spectrophotometrically quantified.
  
  
  RESULTS
  No significant correlations were found between serum DNA concentration and age, histology, response and survival. There was a significant correlation with respect to stage (IIIB = 408.75 ng/ml; IV = 478.74 ng/ml; p = 0.02). When patients were grouped according to DNA concentration, significant correlation with TTP was found; establishing a cut-off point at 500 ng/ml ([DNA] < 500 ng/ml TTP = 7.25 months, 95%CI: 3.5-5.25; [DNA ] > or = 500 ng/ml TTP = 4.25 months, 95%CI: 2-6.5; p = 0.05).
  
  
  CONCLUSIONS
  Using the present method, DNA concentration quantification appears to be simple, but with certain deficiencies due to inter-sample variability and low specificity. This is because total DNA concentration is measured without distinguishing as to whether it is tumour-related. We suggest that there is a correlation between DNA concentration and prognosis which enables an analysis of the natural history of the disease.
authors.affiliation: Servicio de Oncología Médica, Consorcio Hospital General Universitario de Valencia, Av. Tres Cruces s/n, Valencia 46014, Spain. camps_car@gva.es
authors.forename: Carlos
authors.initials: C
authors.lastname: Camps Herrero
authors.forename: Pilar
authors.initials: P
authors.lastname: Bayo Zaera
authors.forename: Rafael
authors.initials: R
authors.lastname: Sirera Pérez
authors.forename: Eva
authors.initials: E
authors.lastname: Sancho Salvador
authors.forename: Ana
authors.initials: A
authors.lastname: Blasco Cordellat
authors.forename: María José
authors.initials: MJ
authors.lastname: Safont Aguilera
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002289:Carcinoma, Non-Small-Cell Lung / Q000097:blood* / Q000235:genetics*; D004273:DNA, Neoplasm / Q000097:blood*; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000097:blood* / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis
chemical_list: D004273:DNA, Neoplasm