title: The carcinoma-stromal ratio of colon carcinoma is an independent factor for survival compared to lymph node status and tumor stage.
abstract: BACKGROUND
  Tumor staging insufficiently discriminates between colon cancer patients with poor and better prognosis. We have evaluated, for the primary tumor, if the carcinoma-percentage (CP), as a derivative from the carcinoma-stromal ratio, can be applied as a candidate marker to identify patients for adjuvant therapy.
  
  
  METHODS
  In a retrospective study of 63 patients with colon cancer (stage I-III, 1990-2001) the carcinoma-percentage of the primary tumor was estimated on routine H&E stained histological sections. Additionally these findings were validated in a second independent study of 59 patients (stage I-III, 1980-1992). (None of the patients had received preoperative chemo- or radiation therapy nor adjuvant chemotherapy.)
  
  
  RESULTS
  Of 122 analyzed patients 33 (27.0%) had a low CP and 89 (73.0%) a high CP. The analysis of mean survival revealed: overall-survival (OS) 2.13 years, disease-free- survival (DFS) 1.51 years for CP-low and OS 7.36 years, DFS 6.89 years for CP-high. Five-year survival rates for CP-low versus CP-high were respectively for OS: 15.2% and 73.0% and for DFS: 12.1% and 67.4%. High levels of significance were found (OS p<0.0001, DFS p<0.0001) with hazard ratio's of 3.73 and 4.18. In a multivariate Cox regression analysis, CP remained an independent variable when adjusted for either stage or for tumor status and lymph-node status (OS p<0.001, OS p<0.001).
  
  
  CONCLUSIONS
  The carcinoma-percentage in primary colon cancer is a factor to discriminate between patients with a poor and a better outcome of disease. This parameter is already available upon routine histological investigation and can, in addition to the TNM classification, be a candidate marker to further stratify into more individual risk groups.
authors.affiliation: Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, The Netherlands. W.E.Mesker@lumc.nl
authors.forename: Wilma E
authors.initials: WE
authors.lastname: Mesker
authors.forename: Jan M C
authors.initials: JM
authors.lastname: Junggeburt
authors.forename: Karoly
authors.initials: K
authors.lastname: Szuhai
authors.forename: Pieter
authors.initials: P
authors.lastname: de Heer
authors.forename: Hans
authors.initials: H
authors.lastname: Morreau
authors.forename: Hans J
authors.initials: HJ
authors.lastname: Tanke
authors.forename: Rob A E M
authors.initials: RA
authors.lastname: Tollenaar
mesh_terms: D000368:Aged; D003110:Colonic Neoplasms / Q000175:diagnosis* / Q000473:pathology* / Q000601:surgery / Q000628:therapy; D003710:Demography; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis; D008297:Male; D053842:Microsatellite Instability; D009367:Neoplasm Staging; D016016:Proportional Hazards Models; D015203:Reproducibility of Results; D017154:Stromal Cells / Q000473:pathology*