title: Clinical outcome of elderly patients with unresectable pancreatic cancer treated with gemcitabine plus S-1, S-1 alone, or gemcitabine alone: Subgroup analysis of a randomised phase III trial, GEST study.
abstract: BACKGROUND
  In the GEST study of unresectable pancreatic cancer, S-1 demonstrated non-inferiority compared to gemcitabine, but gemcitabine plus S-1 (GS) did not show superiority over gemcitabine for overall survival (OS). We performed subgroup analysis of these data focused on the efficacy and safety of these regimens as a first-line treatment for elderly patients.
  
  
  METHODS
  Elderly patients (≥ 70 years, n = 261) treated for unresectable pancreatic cancer (GS: n = 90, S-1: n = 85 and gemcitabine: n = 86) were analysed.
  
  
  RESULTS
  No significant differences between the GS, S-1, or gemcitabine groups in OS (median: 10.2, 8.0 and 8.5 months, respectively) or objective response rates (27.6%, 25.3% and 14.3%, respectively) were noted. Grade ≥ III adverse haematological events were observed more frequently in GS-treated than in S-1- or gemcitabine-treated elderly patients (p < 0.001 and p = 0.016, respectively). Four of 8 patients aged ≥ 80 years experienced serious adverse events.
  
  
  CONCLUSIONS
  S-1 and gemcitabine are both efficacious options for treatment of elderly patients with unresectable pancreatic cancer. Conversely, first-line treatment of elderly patients with GS should only be used after careful consideration.
authors.affiliation: Department of Gastroenterology, Aichi Cancer Center Hospital, Nagoya, Japan. Electronic address: hiroshi.imaoka.md@me.com.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Imaoka
authors.affiliation: Digestive Disease Center, The Tazuke Kofukai Medical Research Institute, Kitano Hospital, Osaka, Japan.
authors.forename: Tadayuki
authors.initials: T
authors.lastname: Kou
authors.affiliation: Department of Surgery and Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Masao
authors.initials: M
authors.lastname: Tanaka
authors.affiliation: Division of Hepato-Biliary-Pancreatic Surgery, Tohoku University Graduate School of Medicine, Sendai, Japan.
authors.forename: Shinichi
authors.initials: S
authors.lastname: Egawa
authors.affiliation: Department of Gastroenterology, Aichi Cancer Center Hospital, Nagoya, Japan.
authors.forename: Nobumasa
authors.initials: N
authors.lastname: Mizuno
authors.affiliation: Department of Gastroenterology, Aichi Cancer Center Hospital, Nagoya, Japan.
authors.forename: Susumu
authors.initials: S
authors.lastname: Hijioka
authors.affiliation: Department of Gastroenterology, Aichi Cancer Center Hospital, Nagoya, Japan.
authors.forename: Kazuo
authors.initials: K
authors.lastname: Hara
authors.affiliation: Digestive Disease Center, The Tazuke Kofukai Medical Research Institute, Kitano Hospital, Osaka, Japan.
authors.forename: Shujiro
authors.initials: S
authors.lastname: Yazumi
authors.affiliation: Department of Gastroenterological Surgery, Aichi Cancer Center Hospital, Nagoya, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Shimizu
authors.affiliation: Department of Gastroenterology, Aichi Cancer Center Hospital, Nagoya, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Yamao
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects / Q000627:therapeutic use*; D003841:Deoxycytidine / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000627:therapeutic use; D018572:Disease-Free Survival; D004338:Drug Combinations; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D010094:Oxonic Acid / Q000009:adverse effects / Q000627:therapeutic use*; D010190:Pancreatic Neoplasms / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology; D016016:Proportional Hazards Models; D012307:Risk Factors; D005641:Tegafur / Q000009:adverse effects / Q000627:therapeutic use*; D013997:Time Factors; D016896:Treatment Outcome; D000093542:Gemcitabine
chemical_list: D004338:Drug Combinations; D003841:Deoxycytidine; C079198:S 1 (combination); D005641:Tegafur; D010094:Oxonic Acid; D000093542:Gemcitabine
keywords: Elderly patients; Gemcitabine; Pancreatic cancer; S-1; Subgroup analysis