title: Circulating DNA and Survival in Solid Tumors.
abstract: BACKGROUND
  The ability to undertake molecular analysis to inform on prognosis and predictors of response to therapy is limited by accessibility of tissue. Measurement of total circulating free DNA (cfDNA) or circulating tumor DNA (ctDNA) in peripheral blood may allow easier access to tumor material and help to predict clinical outcomes.
  
  
  METHODS
  A systematic review of electronic databases identified publications exploring the association between cfDNA or ctDNA and overall survival (OS) in solid tumors. HRs for OS were extracted from multivariable analyses and included in a meta-analysis. Pooled HRs were computed and weighted using generic inverse variance and random-effect modeling. For studies not reporting multivariable analyses, univariable ORs were estimated from Kaplan-Meier curves for OS at 1 and 3 years.
  
  
  RESULTS
  Thirty-nine studies comprising 4,052 patients were included in the analysis. Detection of ctDNA was associated with a significantly worse OS in multivariable analyses [HR, 2.70; 95% confidence interval (CI), 2.02-3.61; P < 0.001). Similar results were observed in the univariable analyses at 3 and 1 year (OR, 4.83; 95% CI, 3.20-7.28; P < 0.001).There was also a statistically significant association between high total cfDNA and worse OS for studies reporting multivariable and univariate data at 3 years (HR, 1.91; 95% CI, 1.59-2.29; P < 0.001 and OR, 2.82; 95% CI, 1.93-4.13; P < 0.001, respectively).
  
  
  CONCLUSIONS
  High levels of total cfDNA and presence of ctDNA are associated with worse survival in solid tumors.
  
  
  CONCLUSIONS
  Circulating DNA is associated with worse outcome in solid tumors.
authors.affiliation: Translational Oncology Unit, Albacete University Hospital, Albacete, Spain. albertoo@sescam.jccm.es.
authors.forename: Alberto
authors.initials: A
authors.lastname: Ocaña
authors.affiliation: Translational Oncology Unit, Albacete University Hospital, Albacete, Spain.
authors.forename: Laura
authors.initials: L
authors.lastname: Díez-González
authors.affiliation: Translational Oncology Unit, Albacete University Hospital, Albacete, Spain.
authors.forename: Dolores C
authors.initials: DC
authors.lastname: García-Olmo
authors.affiliation: Department of Medical Oncology and Hematology, Kantonsspital St. Gallen, St. Gallen, Switzerland.
authors.forename: Arnoud J
authors.initials: AJ
authors.lastname: Templeton
authors.affiliation: Divisions of Medical Oncology and Hematology, Princess Margaret Cancer Centre, Department of Medicine, University of Toronto, Toronto, Canada.
authors.forename: Francisco
authors.initials: F
authors.lastname: Vera-Badillo
authors.affiliation: Translational Oncology Unit, Albacete University Hospital, Albacete, Spain.
authors.forename: María
authors.initials: M
authors.lastname: José Escribano
authors.affiliation: Translational Oncology Unit, Albacete University Hospital, Albacete, Spain.
authors.forename: Gemma
authors.initials: G
authors.lastname: Serrano-Heras
authors.affiliation: Translational Oncology Unit, Albacete University Hospital, Albacete, Spain.
authors.forename: Verónica
authors.initials: V
authors.lastname: Corrales-Sánchez
authors.affiliation: Department of Medical Oncology, Institute of Oncology Ljubljana, Ljubljana, Slovenia.
authors.forename: Bostjan
authors.initials: B
authors.lastname: Seruga
authors.affiliation: Translational Oncology Unit, Albacete University Hospital, Albacete, Spain.
authors.forename: Fernando
authors.initials: F
authors.lastname: Andrés-Pretel
authors.affiliation: IBMCC-CSIC, Universidad de Salamanca, Salamanca, Spain.
authors.forename: Atanasio
authors.initials: A
authors.lastname: Pandiella
authors.affiliation: Divisions of Medical Oncology and Hematology, Princess Margaret Cancer Centre, Department of Medicine, University of Toronto, Toronto, Canada.
authors.forename: Eitan
authors.initials: E
authors.lastname: Amir
mesh_terms: D004247:DNA / Q000235:genetics*; D006801:Humans; D009369:Neoplasms / Q000401:mortality; D011379:Prognosis
chemical_list: D004247:DNA