title: Significance of isolated tumor cells in lymph nodes among gastric cancer patients.
abstract: OBJECTIVE
  To determine the frequency and prognostic impact of isolated tumor cells (ITC) in regional lymph nodes judged to be tumor free in conventional histopathology among gastric cancer patients.
  
  
  METHODS
  Among 161 patients who underwent gastrectomy and D2-lymphadenectomy, 56 were staged pN0(35%). Archival paraffin blocks of 1148 resected regional lymph nodes of those pN0 patients were reevaluated for ITC using monoclonal antibody Ber-EP4. Patients with and without ITC were compared with regard to the distribution of various clinicopathological factors. Prognostic impact of ITC was tested in uni- and multivariate analysis.
  
  
  RESULTS
  Of 56 pN0 patients, 33 (59%) exhibited single Ber-Ep4 immunoreactive cells or small cell clusters in at least one lymph node. The occurrence of ITC was not dependent on other clinicopathological factors. ITC impaired patients' prognoses significantly in uni- as well as multivariate analyses [estimated 5-year survival rate: 82% for pN0((i-))vs 58% for pN0((i+))(p = 0.059) and 15% for pN1/2 (p = 0.0005 and p < 0.0001, respectively)].
  
  
  CONCLUSIONS
  ITC are a frequent event in apparently tumor-free lymph nodes of gastric cancer patients and are overlooked by conventional histopathology. They are encountered even in limited stages of disease and impair patients' prognoses. This should be borne in mind when advocating local resection for early gastric cancer.
authors.affiliation: Klinik für Allgemeinchirurgie, Universitätsklinikum Göttingen, Germany. ohorstmann@surgery-goettingen.de
authors.forename: Olaf
authors.initials: O
authors.lastname: Horstmann
authors.forename: Laszlo
authors.initials: L
authors.lastname: Füzesi
authors.forename: Peter M
authors.initials: PM
authors.lastname: Markus
authors.forename: Carola
authors.initials: C
authors.lastname: Werner
authors.forename: Heinz
authors.initials: H
authors.lastname: Becker
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D017730:Ki-1 Antigen / Q000032:analysis*; D008197:Lymph Node Excision; D008198:Lymph Nodes / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011379:Prognosis; D013274:Stomach Neoplasms / Q000401:mortality / Q000473:pathology*; D015996:Survival Rate
chemical_list: D017730:Ki-1 Antigen