title: Exploring gene expression signatures for predicting disease free survival after resection of colorectal cancer liver metastases.
abstract: OBJECTIVE
  This study was designed to identify and validate gene signatures that can predict disease free survival (DFS) in patients undergoing a radical resection for their colorectal liver metastases (CRLM).
  
  
  METHODS
  Tumor gene expression profiles were collected from 119 patients undergoing surgery for their CRLM in the Paul Brousse Hospital (France) and the University Medical Center Utrecht (The Netherlands). Patients were divided into high and low risk groups. A randomly selected training set was used to find predictive gene signatures. The ability of these gene signatures to predict DFS was tested in an independent validation set comprising the remaining patients. Furthermore, 5 known clinical risk scores were tested in our complete patient cohort.
  
  
  RESULTS
  No gene signature was found that significantly predicted DFS in the validation set. In contrast, three out of five clinical risk scores were able to predict DFS in our patient cohort.
  
  
  CONCLUSIONS
  No gene signature was found that could predict DFS in patients undergoing CRLM resection. Three out of five clinical risk scores were able to predict DFS in our patient cohort. These results emphasize the need for validating risk scores in independent patient groups and suggest improved designs for future studies.
authors.affiliation: Department of Surgery, University Medical Center Utrecht, Heidelberglaan 100, Utrecht, The Netherlands.
authors.forename: Nikol
authors.initials: N
authors.lastname: Snoeren
authors.forename: Sander R
authors.initials: SR
authors.lastname: van Hooff
authors.forename: Rene
authors.initials: R
authors.lastname: Adam
authors.forename: Richard
authors.initials: R
authors.lastname: van Hillegersberg
authors.forename: Emile E
authors.initials: EE
authors.lastname: Voest
authors.forename: Catherine
authors.initials: C
authors.lastname: Guettier
authors.forename: Paul J
authors.initials: PJ
authors.lastname: van Diest
authors.forename: Maarten W
authors.initials: MW
authors.lastname: Nijkamp
authors.forename: Mariel O
authors.initials: MO
authors.lastname: Brok
authors.forename: Dik
authors.initials: D
authors.lastname: van Leenen
authors.forename: Marian J A Groot
authors.initials: MJ
authors.lastname: Koerkamp
authors.forename: Frank C P
authors.initials: FC
authors.lastname: Holstege
authors.forename: Inne H M Borel
authors.initials: IH
authors.lastname: Rinkes
mesh_terms: D000368:Aged; D019540:Area Under Curve; D015331:Cohort Studies; D015179:Colorectal Neoplasms / Q000378:metabolism / Q000473:pathology*; D018572:Disease-Free Survival; D005260:Female; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008113:Liver Neoplasms / Q000378:metabolism / Q000556:secondary*; D008297:Male; D008875:Middle Aged; D009693:Nucleic Acid Hybridization; D020411:Oligonucleotide Array Sequence Analysis; D016016:Proportional Hazards Models; D012008:Recurrence; D012306:Risk; D016896:Treatment Outcome