title: Isolated tumor cells in stage I & II colon cancer patients are associated with significantly worse disease-free and overall survival.
abstract: BACKGROUND
  Lymph node (LN) involvement represents the strongest prognostic factor in colon cancer patients. The objective of this prospective study was to assess the prognostic impact of isolated tumor cells (ITC, defined as cell deposits ≤ 0.2 mm) in loco-regional LN of stage I & II colon cancer patients.
  
  
  METHODS
  Seventy-four stage I & II colon cancer patients were prospectively enrolled in the present study. LN at high risk of harboring ITC were identified via an in vivo sentinel lymph node procedure and analyzed with multilevel sectioning, conventional H&E and immunohistochemical CK-19 staining. The impact of ITC on survival was assessed using Cox regression analyses.
  
  
  RESULTS
  Median follow-up was 4.6 years. ITC were detected in locoregional lymph nodes of 23 patients (31.1%). The presence of ITC was associated with a significantly worse disease-free survival (hazard ratio = 4.73, p = 0.005). Similarly, ITC were associated with significantly worse overall survival (hazard ratio = 3.50, p = 0.043).
  
  
  CONCLUSIONS
  This study provides compelling evidence that ITC in stage I & II colon cancer patients are associated with significantly worse disease-free and overall survival. Based on these data, the presence of ITC should be classified as a high risk factor in stage I & II colon cancer patients who might benefit from adjuvant chemotherapy.
authors.affiliation: Department of Surgery, Kantonsspital Olten, Baslerstrasse 150, CH - 4600, Olten, Switzerland.|Department of Surgery, University Hospital Basel, Basel, Switzerland.
authors.forename: B
authors.initials: B
authors.lastname: Weixler
authors.affiliation: Department of Surgery, Kantonsspital St. Gallen, St. Gallen, Switzerland.|Institute of Medical Biometry and Informatics, University of Heidelberg, Heidelberg, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Warschkow
authors.affiliation: Department of Oncology/Hematology, Kantonsspital St. Gallen, St. Gallen, Switzerland.|University Clinic for Visceral Surgery and Medicine, Inselspital Berne, University of Berne, Berne, Switzerland.
authors.forename: U
authors.initials: U
authors.lastname: Güller
authors.affiliation: Viollier AG, Histopathology/Cytology, Basel, Switzerland.
authors.forename: A
authors.initials: A
authors.lastname: Zettl
authors.affiliation: Department of Surgery, University Hospital Basel, Basel, Switzerland.
authors.forename: U
authors.initials: U
authors.lastname: von Holzen
authors.affiliation: Department of Surgery, Kantonsspital St. Gallen, St. Gallen, Switzerland.
authors.forename: B M
authors.initials: BM
authors.lastname: Schmied
authors.affiliation: Department of Surgery, Kantonsspital Olten, Baslerstrasse 150, CH - 4600, Olten, Switzerland. markus.zuber@spital.so.ch.
authors.forename: M
authors.initials: M
authors.lastname: Zuber
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003110:Colonic Neoplasms / Q000453:epidemiology / Q000401:mortality* / Q000473:pathology*; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008198:Lymph Nodes / Q000473:pathology; D008207:Lymphatic Metastasis / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies