title: Detection of disseminated tumour cells in blood and bone marrow samples of patients undergoing hepatic resection for metastasis of colorectal cancer.
abstract: BACKGROUND
  In 50-60 per cent of patients who undergo hepatic resection for metastasis of colorectal cancer the first site of tumour recurrence is extrahepatic, indicating the presence of more extensive disease at the time of resection. The aim of this study was to evaluate whether the presence of disseminated tumour cells in blood and bone marrow could predict extrahepatic tumour recurrence.
  
  
  METHODS
  Cytokeratin 20 (CK20) reverse transcriptase-polymerase chain reaction was used to study the presence of tumour cells in preoperative peripheral blood and bone marrow samples from 41 patients with liver metastasis scheduled for surgical resection.
  
  
  RESULTS
  CK20 expression was detected in six of 41 peripheral blood samples and in eight of 32 bone marrow samples. There was no correlation between CK20-positive samples and subsequent extrahepatic recurrence. Positive blood samples did, however, correlate with high serum carcinoembryonic antigen level and large tumour volume. None of the 14 patients previously treated with chemotherapy had CK20-positive samples, whereas six of 27 blood and eight of 20 bone marrow samples were positive in the chemotherapy-naive group.
  
  
  CONCLUSIONS
  Although the number of patients in this study is limited, the presence of disseminated tumour cells did not predict subsequent extrahepatic recurrence. The results strongly suggest that the presence of circulating tumour cells in peripheral blood may reflect transient shedding of tumour cells related to large tumour volume.
authors.affiliation: Department of Surgery, University Medical Centre Nijmegen, Nijmegen, The Netherlands. f.vlems@pathol.umcn.nl
authors.forename: F A
authors.initials: FA
authors.lastname: Vlems
authors.forename: J H S
authors.initials: JH
authors.lastname: Diepstra
authors.forename: C J A
authors.initials: CJ
authors.lastname: Punt
authors.forename: M J L
authors.initials: MJ
authors.lastname: Ligtenberg
authors.forename: I M H A
authors.initials: IM
authors.lastname: Cornelissen
authors.forename: J H J M
authors.initials: JH
authors.lastname: van Krieken
authors.forename: T
authors.initials: T
authors.lastname: Wobbes
authors.forename: G N P
authors.initials: GN
authors.lastname: van Muijen
authors.forename: T J M
authors.initials: TJ
authors.lastname: Ruers
mesh_terms: D000328:Adult; D000368:Aged; D019046:Bone Marrow Neoplasms / Q000556:secondary*; D015179:Colorectal Neoplasms / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D007381:Intermediate Filament Proteins / Q000097:blood / Q000378:metabolism; D053554:Keratin-20; D008113:Liver Neoplasms / Q000473:pathology / Q000556:secondary*; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000473:pathology; D009360:Neoplastic Cells, Circulating / Q000473:pathology*; D016133:Polymerase Chain Reaction / Q000379:methods
chemical_list: D007381:Intermediate Filament Proteins; C507499:KRT20 protein, human; D053554:Keratin-20