title: Efficacy of trastuzumab in Japanese patients with HER2-positive advanced gastric or gastroesophageal junction cancer: a subgroup analysis of the Trastuzumab for Gastric Cancer (ToGA) study.
abstract: BACKGROUND
  The Trastuzumab for Gastric Cancer (ToGA) study is the first international trial to include Japanese patients with human epidermal growth factor 2 (HER2) positive advanced/metastatic gastric or gastroesophageal junction cancer. ToGA showed that trastuzumab plus chemotherapy (capecitabine/cisplatin or 5-fluorouracil/cisplatin) improved overall survival in the overall population (hazard ratio 0.74). Regional differences in outcome in favor of Japanese populations were observed in other studies; therefore, subgroup analyses of ToGA may contribute to the evaluation of the potential benefits of this regimen in Japanese patients.
  
  
  METHODS
  We performed subgroup analyses on 101 Japanese patients enrolled into ToGA (trastuzumab plus chemotherapy, n = 51; chemotherapy, n = 50).
  
  
  RESULTS
  Median overall survival in the Japanese subgroup was 15.9 months (95% confidence interval 12-25) for trastuzumab plus chemotherapy and 17.7 months (95% confidence interval 12-24) for chemotherapy (hazard ratio 1.00; 95% confidence interval 0.59-1.69). After adjusting for prespecified covariates, the estimated hazard ratio for overall survival was 0.68 (95% confidence interval 0.36-1.27). Further post hoc and exploratory examinations supported the robustness of the adjusted hazard ratios.
  
  
  CONCLUSIONS
  After adjusting for imbalanced patient backgrounds between arms, overall survival of Japanese patients with human epidermal growth factor 2 positive advanced/metastatic gastric or gastroesophageal junction cancer who received trastuzumab plus chemotherapy was improved compared with patients who received chemotherapy alone.
authors.affiliation: Department of Gastroenterology, Aichi Cancer Center Hospital, Aichi, Japan. sawaki@jk2.so-net.ne.jp
authors.forename: Akira
authors.initials: A
authors.lastname: Sawaki
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Ohashi
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Omuro
authors.forename: Taroh
authors.initials: T
authors.lastname: Satoh
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Hamamoto
authors.forename: Narikazu
authors.initials: N
authors.lastname: Boku
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Miyata
authors.forename: Hiroya
authors.initials: H
authors.lastname: Takiuchi
authors.forename: Kensei
authors.initials: K
authors.lastname: Yamaguchi
authors.forename: Yasutsuna
authors.initials: Y
authors.lastname: Sasaki
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Nishina
authors.forename: Atsushi
authors.initials: A
authors.lastname: Satoh
authors.forename: Eishi
authors.initials: E
authors.lastname: Baba
authors.forename: Takao
authors.initials: T
authors.lastname: Tamura
authors.forename: Takashi
authors.initials: T
authors.lastname: Abe
authors.forename: Kiyohiko
authors.initials: K
authors.lastname: Hatake
authors.forename: Atsushi
authors.initials: A
authors.lastname: Ohtsu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D061067:Antibodies, Monoclonal, Humanized / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects / Q000627:therapeutic use*; D044466:Asian People; D000069287:Capecitabine; D002945:Cisplatin / Q000008:administration & dosage; D003841:Deoxycytidine / Q000008:administration & dosage / Q000031:analogs & derivatives; D004938:Esophageal Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000401:mortality*; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage / Q000031:analogs & derivatives; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D016016:Proportional Hazards Models; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000235:genetics / Q000378:metabolism*; D013274:Stomach Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000401:mortality*; D015996:Survival Rate; D000068878:Trastuzumab
chemical_list: D061067:Antibodies, Monoclonal, Humanized; D000069287:Capecitabine; D002945:Cisplatin; D003841:Deoxycytidine; D005472:Fluorouracil; D018719:Erb-b2 Receptor Tyrosine Kinases; D000068878:Trastuzumab; C508053:ERBB2 protein, human