title: The proportion of tumor-stroma as a strong prognosticator for stage II and III colon cancer patients: validation in the VICTOR trial.
abstract: BACKGROUND
  The intra-tumor stroma percentage in colon cancer (CC) patients has previously been reported by our group as a strong independent prognostic parameter. Patients with a high stroma percentage within the primary tumor have a poor prognosis.
  
  
  METHODS
  Tissue samples from the most invasive part of the primary tumor of 710 patients (52% Stage II, 48% Stage III) participating in the VICTOR trial were analyzed for their tumor-stroma percentage. Stroma-high (>50%) and stroma-low (≤50%) groups were evaluated with respect to survival times.
  
  
  RESULTS
  Overall and disease-free survival times (OS and DFS) were significantly lower in the stroma-high group (OS P<0.0001, hazard ratio (HR)=1.96; DFS P<0.0001, HR=2.15). The 5-year OS was 69.0% versus 83.4% and DFS 58.6% versus 77.3% for stroma-high versus stroma-low patients.
  
  
  CONCLUSIONS
  This study confirms the intra-tumor stroma ratio as a prognostic factor. This parameter could be a valuable and low cost addition to the TNM status and next to current high-risk parameters such as microsatellite instability status used in routine pathology reporting. When adding the stroma-parameter to the ASCO criteria, the rate of 'undertreated' patients dropped from 5.9% to 4.3%, the 'overtreated' increased with 6.8% but the correctly classified increased with an additional 14%.
authors.affiliation: Department of Surgery, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: A
authors.initials: A
authors.lastname: Huijbers
authors.forename: R A E M
authors.initials: RA
authors.lastname: Tollenaar
authors.forename: G W
authors.initials: GW
authors.lastname: v Pelt
authors.forename: E C M
authors.initials: EC
authors.lastname: Zeestraten
authors.forename: S
authors.initials: S
authors.lastname: Dutton
authors.forename: C C
authors.initials: CC
authors.lastname: McConkey
authors.forename: E
authors.initials: E
authors.lastname: Domingo
authors.forename: V T H B M
authors.initials: VT
authors.lastname: Smit
authors.forename: R
authors.initials: R
authors.lastname: Midgley
authors.forename: B F
authors.initials: BF
authors.lastname: Warren
authors.forename: E C
authors.initials: EC
authors.lastname: Johnstone
authors.forename: D J
authors.initials: DJ
authors.lastname: Kerr
authors.forename: W E
authors.initials: WE
authors.lastname: Mesker
mesh_terms: D003110:Colonic Neoplasms / Q000473:pathology*; D004311:Double-Blind Method; D006801:Humans; D011379:Prognosis; D017154:Stromal Cells / Q000473:pathology*; D016019:Survival Analysis