title: Updated results from GEST study: a randomized, three-arm phase III study for advanced pancreatic cancer.
abstract: OBJECTIVE
  The GEST study showed non-inferiority of S-1 but not superiority of gemcitabine plus S-1 (GS) to gemcitabine alone for overall survival with the data by the cut-off date of 31st July in 2010 for chemo-naïve patients with advanced pancreatic cancer. We considered it important to determine whether S-1 maintains non-inferiority after a long-term follow-up in the GEST study and to obtain a firm positive conclusion. In addition, it may be an interesting challenge to explore the efficacious profile of GS in the long-term follow-up study. Using the data from the follow-up period, background and efficacy in patients from Taiwan and Japan, as well as the rates of tumor shrinkage in locally advanced and metastatic patients (Waterfall plot) were also analyzed.
  
  
  METHODS
  The results of the primary analysis were reconfirmed, and subset analysis of overall survival and progression-free survival was performed based on the overall survival data updated by the cut-off date of 31st July in 2011.
  
  
  RESULTS
  The median follow-up period was 29.8 months, and 795 deaths occurred (95.6%). The median overall survival was 8.8 months for gemcitabine, 9.7 months for S-1 (hazard ratio [HR], 0.96; 97.5% confidence interval [CI], 0.79-1.17), and 9.9 months for GS (HR 0.91; 97.5% CI 0.75-1.11). In patients with performance status (PS) 0, the median overall survival was 9.8 months for gemcitabine, 10.9 months for S-1, and 10.5 months for GS. In patients with PS 1, the median overall survival was 6.2 months for gemcitabine, 6.3 months for S-1, and 9.6 months for GS.
  
  
  CONCLUSIONS
  Our survey reconfirmed the non-inferiority of S-1 to gemcitabine and showed S-1 can be used as one of the standard treatment options for advanced pancreatic cancer.
  
  
  BACKGROUND
  ClinicalTrials.gov: NCT00498225.
authors.affiliation: Department of Hepatobiliary and Pancreatic Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan. tokusaka@ncc.go.jp.
authors.forename: Takuji
authors.identifier: http://orcid.org/0000-0003-1729-807X
authors.initials: T
authors.lastname: Okusaka
authors.affiliation: Division of Biliopancreatology, Sapporo Kosei General Hospital, Sapporo, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Miyakawa
authors.affiliation: Division of Clinical Oncology, Jichi Medical University, Tochigi, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Fujii
authors.affiliation: Hepato-Biliary-Pancreatic Surgery, Osaka National Hospital, Osaka, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Nakamori
authors.affiliation: Department of Frontier Science for Cancer and Chemotherapy, Osaka University Graduate School of Medicine, Suita, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Satoh
authors.affiliation: Keio Cancer Center, Keio University Hospital, Tokyo, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Hamamoto
authors.affiliation: Department of Medicine and Bioreguratory Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Ito
authors.affiliation: Center for Gastroenterology, Teine-Keijinkai Hospital, Sapporo, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Maguchi
authors.affiliation: Department of Medical Oncology, Kyoto University Hospital, Kyoto, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Matsumoto
authors.affiliation: Department of Hepatobiliary and Pancreatic Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Ueno
authors.affiliation: Department of Hepatobiliary and Pancreatic Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Ioka
authors.affiliation: Gastrointestinal Medical Oncology Division, National Cancer Center Hospital, Tokyo, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Boku
authors.affiliation: Department of Surgery, Tohoku University, Sendai, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Egawa
authors.affiliation: Department of Surgery and Digestive Diseases Center, International University of Health and Welfare Mita Hospital, Tokyo, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Hatori
authors.affiliation: Department of Medical Oncology, Kyorin University School of Medicine, Tokyo, Japan.
authors.forename: J
authors.initials: J
authors.lastname: Furuse
authors.affiliation: Kyushu University Hospital Cancer Center, Fukuoka, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Mizumoto
authors.affiliation: Division of Hepatobiliary and Pancreatic Oncology, Kanagawa Cancer Center, Yokohama, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Ohkawa
authors.affiliation: Department of Gastroenterology, Chiba Cancer Center, Chiba, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Yamaguchi
authors.affiliation: Department of Gastroenterology, Aichi Cancer Center Hospital, Nagoya, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Yamao
authors.affiliation: Division of Pancreatology, Fukuoka Sanno Hospital, Fukuoka, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Funakoshi
authors.affiliation: Division of Hematology-Oncology, Linkou Chang Gung Memorial Hospital and Chang Gung University, Tao-Yuan, Taiwan, Republic of China.
authors.forename: J S
authors.initials: JS
authors.lastname: Chen
authors.affiliation: Department of Oncology, National Taiwan University Hospital, and National Taiwan University Cancer Center, Taipei, Taiwan, Republic of China.
authors.forename: A L
authors.initials: AL
authors.lastname: Cheng
authors.affiliation: Department of Medical Oncology, Hirosaki University Graduate School of Medicine, Aomori, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Sato
authors.affiliation: Department of Integrated Science and Engineering for Sustainable Society, Chuo University, Tokyo, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Ohashi
authors.affiliation: Department of Surgery, Shimonoseki City Hospital, Shimonoseki, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Tanaka
mesh_terms: D000230:Adenocarcinoma / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D003841:Deoxycytidine / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives*; D018450:Disease Progression; D004338:Drug Combinations; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D010094:Oxonic Acid / Q000008:administration & dosage* / Q000009:adverse effects; D010190:Pancreatic Neoplasms / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology; D005641:Tegafur / Q000008:administration & dosage* / Q000009:adverse effects; D000093542:Gemcitabine
chemical_list: D004338:Drug Combinations; D003841:Deoxycytidine; C079198:S 1 (combination); D005641:Tegafur; D010094:Oxonic Acid; D000093542:Gemcitabine
keywords: Gemcitabine; Pancreatic cancer; S-1; Subgroup analysis; Updated data