title: Disseminated tumor cells in the blood of patients with gastric cancer are an independent predictive marker of poor prognosis.
abstract: OBJECTIVE
  Gastric cancer carries a poor prognosis even after curative resection (R0). Tumor progression in gastric cancer patients has been attributed to the persistence of disseminated tumor cells (DTC) in various body compartments as a sign of minimal residual disease, although the prognostic relevance of DTC is still unclear. In this study the prognostic relevance of DTC in the blood of gastric cancer patients was investigated.
  
  
  METHODS
  Venous blood samples of 70 cancer patients were taken intraoperatively before surgical manipulation and examined by reverse transcription-polymerase chain reaction (RT-PCR) for expression of cytokeratin 20 (CK20) as a marker for DTC. Tumor-related survival was analyzed using univariate and multivariate models assessing occurrence of DTC, residual tumor classification, and tumor stage. Median follow-up was 20 months (range 1-57 months).
  
  
  RESULTS
  Twenty-eight of the 70 patients (40%) were CK20 positive. The prevalence of DTC in patients following R0 resection (15/41, 37%) was similar to that in patients with residual tumor (13/29, 45%, NS). Furthermore, expression of CK20 was independent of TNM stage. Univariate analysis of R0-resected patients revealed CK20 to be a marker for significantly shorter tumor-related survival (p = 0.0363). In a multivariate analysis, CK20 was an independent prognostic marker. Detection of CK20 had greatest impact for early tumor stages (T1 and T2, N0; p < 0.0032).
  
  
  CONCLUSIONS
  Detection of DTC in venous blood of gastric cancer patients is an independent predictive marker of poor prognosis and thus could help to define patients for adjuvant therapy with this tumor entity.
authors.affiliation: Department of Surgery, University of Würzburg, Germany. illert_b@chirurgie.uni-wuerzburg.de
authors.forename: Bertram
authors.initials: B
authors.lastname: Illert
authors.forename: Martin
authors.initials: M
authors.lastname: Fein
authors.forename: Christoph
authors.initials: C
authors.lastname: Otto
authors.forename: Florian
authors.initials: F
authors.lastname: Cording
authors.forename: Dominik
authors.initials: D
authors.lastname: Stehle
authors.forename: Arnulf
authors.initials: A
authors.lastname: Thiede
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Timmermann
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001483:Base Sequence; D014408:Biomarkers, Tumor / Q000097:blood*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007381:Intermediate Filament Proteins / Q000235:genetics / Q000378:metabolism*; D053554:Keratin-20; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D015999:Multivariate Analysis; D009366:Neoplasm Seeding; D009367:Neoplasm Staging; D009360:Neoplastic Cells, Circulating / Q000378:metabolism*; D011237:Predictive Value of Tests; D011300:Preoperative Care; D011379:Prognosis; D011446:Prospective Studies; D012334:RNA, Neoplasm / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D018570:Risk Assessment; D013274:Stomach Neoplasms / Q000097:blood* / Q000401:mortality* / Q000473:pathology / Q000601:surgery; D016019:Survival Analysis
chemical_list: D014408:Biomarkers, Tumor; D007381:Intermediate Filament Proteins; C507499:KRT20 protein, human; D053554:Keratin-20; D012334:RNA, Neoplasm