title: Prognostic significance of intraperitoneal cancer cells in gastric carcinoma: detection of cytokeratin 20 mRNA in peritoneal washes, in addition to detection of carcinoembryonic antigen.
abstract: BACKGROUND
  In patients with gastric cancer, the presence of gastric cancer cells in the peritoneal cavity detected by cytologic examination, is a significant prognostic factor. A more sensitive, reverse transcriptase-polymerase chain reaction (RT-PCR) technique, amplifying carcinoembryonic antigen (CEA), was introduced as a new detection system, but produced some false-positive results. A search for other molecular markers is ongoing.
  
  
  METHODS
  Peritoneal washes were obtained from 195 patients with gastric carcinoma during surgery. Cytokeratin 20 (CK20) mRNA levels were quantified, in addition to those of CEA, using the LightCycler, and the feasibility of CK20 as a target was evaluated.
  
  
  RESULTS
  CK20 was limited, in terms of sensitivity, for detecting disseminated cancer cells (sensitivity, 63%; specificity, 91%; positive predictive value, 70%; and negative predictive value, 88%). Multimarker analysis was performed, in which samples positive for either CK20 or CEA mRNA were considered to be positive for cancer cells. Multivariate analysis identified the multimarker analysis as a significant independent prognostic determinant.
  
  
  CONCLUSIONS
  CK20 RT-PCR produced information that could add a significant impact to the knowledge obtained by CEA RT-PCR, although detection by CK20 alone was not sufficiently sensitive to replace CEA in the detection system.
authors.affiliation: Second Department of Surgery, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Kodera
authors.forename: Hayao
authors.initials: H
authors.lastname: Nakanishi
authors.forename: Seiji
authors.initials: S
authors.lastname: Ito
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Yamamura
authors.forename: Michitaka
authors.initials: M
authors.lastname: Fujiwara
authors.forename: Masahiko
authors.initials: M
authors.lastname: Koike
authors.forename: Kenji
authors.initials: K
authors.lastname: Hibi
authors.forename: Katsuki
authors.initials: K
authors.lastname: Ito
authors.forename: Masae
authors.initials: M
authors.lastname: Tatematsu
authors.forename: Akimasa
authors.initials: A
authors.lastname: Nakao
mesh_terms: D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism; D002272:Carcinoembryonic Antigen / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D007381:Intermediate Filament Proteins / Q000235:genetics* / Q000378:metabolism; D053554:Keratin-20; D008207:Lymphatic Metastasis / Q000175:diagnosis; D009361:Neoplasm Invasiveness / Q000175:diagnosis; D009367:Neoplasm Staging; D010533:Peritoneal Lavage; D010534:Peritoneal Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000556:secondary; D011379:Prognosis; D012333:RNA, Messenger / Q000032:analysis*; D012334:RNA, Neoplasm / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012680:Sensitivity and Specificity; D013274:Stomach Neoplasms / Q000235:genetics* / Q000378:metabolism; D015996:Survival Rate
chemical_list: D014408:Biomarkers, Tumor; D002272:Carcinoembryonic Antigen; D007381:Intermediate Filament Proteins; C507499:KRT20 protein, human; D053554:Keratin-20; D012333:RNA, Messenger; D012334:RNA, Neoplasm