title: Prediction of lymphatic invasion/lymph node metastasis, recurrence, and survival in patients with gastric cancer by cDNA array-based expression profiling.
abstract: BACKGROUND
  We assessed the predictability of various classes of gastric carcinoma defined by clinicopathological parameters, such as invasiveness and clinical outcomes, using cDNA array data obtained from 54 cases.
  
  
  METHODS
  We searched an optimal combination of genes to discriminate the classes defined with the clinicopathological parameters by using a feature subset selection algorithm, which was applied to a set of genes preselected on the basis of statistical difference in expression (two-sided t test, P < or = 0.05). With the selected features (gene set), we evaluated the predictability of each parameter in a leave-one-out cross-validation test.
  
  
  RESULTS
  We successfully selected sets of genes for which the classifier predicted better versus worse overall survival (tumor-specific death) and tumor-free survival (recurrence), with respective classification rates of 94 and 92%. A contingency table analysis (chi2 test) and Cox proportional hazard model analysis revealed that lymph node metastasis is the most important factor (confounding factor) in patients' prognoses and risks of recurrence. The feature subset selection procedure successfully extracted expression patterns characteristic of lymph node metastasis and lymphatic vessel invasion, yielding 92 and 98% prediction accuracies for these respective factors.
  
  
  CONCLUSIONS
  We conclude that expression profiling using feature subset selection provides a powerful means of stratification of gastric cancer patients in regard to the prognostic factors. Further studies should be warranted to apply this method to personalization of the treatment options.
authors.affiliation: Department of Pathology/Pathophysiology, Division of Pathophysiological Science, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Teramoto
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Tada
authors.forename: Eiji
authors.initials: E
authors.lastname: Tamoto
authors.forename: Motoki
authors.initials: M
authors.lastname: Abe
authors.forename: Akiko
authors.initials: A
authors.lastname: Kawakami
authors.forename: Kazuteru
authors.initials: K
authors.lastname: Komuro
authors.forename: Akihiro
authors.initials: A
authors.lastname: Matsunaga
authors.forename: Gaku
authors.initials: G
authors.lastname: Shindoh
authors.forename: Minoru
authors.initials: M
authors.lastname: Takada
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Murakawa
authors.forename: Motoshi
authors.initials: M
authors.lastname: Kanai
authors.forename: Nozomi
authors.initials: N
authors.lastname: Kobayashi
authors.forename: Yoshie
authors.initials: Y
authors.lastname: Fujiwara
authors.forename: Norihiro
authors.initials: N
authors.lastname: Nishimura
authors.forename: Katsutoshi
authors.initials: K
authors.lastname: Shirata
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Takahishi
authors.forename: Akihiro
authors.initials: A
authors.lastname: Ishizu
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Ikeda
authors.forename: Jun-ichi
authors.initials: J
authors.lastname: Hamada
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kondo
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Katoh
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Moriuchi
authors.forename: Takashi
authors.initials: T
authors.lastname: Yoshiki
mesh_terms: D002288:Adenocarcinoma, Mucinous / Q000235:genetics / Q000401:mortality / Q000556:secondary; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D020132:Anticipation, Genetic; D002291:Carcinoma, Papillary / Q000235:genetics* / Q000401:mortality / Q000556:secondary*; D018279:Carcinoma, Signet Ring Cell / Q000235:genetics / Q000401:mortality / Q000556:secondary; D005260:Female; D020869:Gene Expression Profiling / Q000379:methods; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008207:Lymphatic Metastasis / Q000235:genetics* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000235:genetics* / Q000401:mortality; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods*; D011237:Predictive Value of Tests; D011379:Prognosis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013274:Stomach Neoplasms / Q000235:genetics* / Q000401:mortality / Q000556:secondary*; D016019:Survival Analysis