title: Risk Factors for Gallstone Formation after Surgery for Gastric Cancer.
abstract: OBJECTIVE
  The incidence of gallstones after gastrectomy for gastric cancer is higher than in the general population. However, the causes and mechanisms of post-gastrectomy gallstones are unclear. The aim of this study was to evaluate the incidence of gallstone formation and the risk factors for their development after gastrectomy for gastric cancer.
  
  
  METHODS
  Of 1,744 gastric cancer patients who underwent gastrectomy at Seoul National University Bundang Hospital between January 2010 and December 2012, 1,284 were included in this study and retrospectively reviewed. Patients' age, sex, body mass index (BMI), tumor location, stage, type of gastrectomy, type of reconstruction, and extent of node dissection were evaluated.
  
  
  RESULTS
  The incidence of gallstones after gastrectomy for gastric cancer was significantly higher in men than in women (P=0.019). Exclusion of the duodenum during reconstruction was associated with a significantly higher incidence of gallstones (P=0.003). Overweight and obese patients with BMI ≥23 kg/m(2) had significantly higher incidence of gallstones than those with a lower BMI (P=0.006). Multivariate analysis showed that obesity (hazard ratio, HR=1.614; 95% confidence interval, CI: 1.135~2.296; P=0.008), male sex (HR=1.515, 95% CI: 1.029~2.231, P=0.033), and exclusion of the duodenum (HR=1.648, 95% CI: 1.192~2.280, P=0.003) were significant, independent risk factors for gallstones after gastrectomy.
  
  
  CONCLUSIONS
  The cumulative incidence of gallstones for 5 years after gastrectomy was 15.3%. Male sex, obesity, and exclusion of the duodenum were risk factors for gallstone formation after gastrectomy. Careful surveillance will be required for these patient groups after gastrectomy.
authors.affiliation: Department of Surgery, Seoul National University Bundang Hospital, Seongnam, Korea.
authors.forename: Dong Jin
authors.initials: DJ
authors.lastname: Park
authors.affiliation: Department of Surgery, Seoul National University Bundang Hospital, Seongnam, Korea.
authors.forename: Ki Hyun
authors.initials: KH
authors.lastname: Kim
authors.affiliation: Department of Surgery, Seoul National University Bundang Hospital, Seongnam, Korea.
authors.forename: Young Suk
authors.initials: YS
authors.lastname: Park
authors.affiliation: Department of Surgery, Seoul National University Bundang Hospital, Seongnam, Korea.; Department of Surgery, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Sang-Hoon
authors.initials: SH
authors.lastname: Ahn
authors.affiliation: Department of Surgery, Seoul National University Bundang Hospital, Seongnam, Korea.; Department of Surgery, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Do Joong
authors.initials: do J
authors.lastname: Park
authors.affiliation: Department of Surgery, Seoul National University Bundang Hospital, Seongnam, Korea.; Department of Surgery, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Hyung-Ho
authors.initials: HH
authors.lastname: Kim
keywords: Gallstones; Gastrectomy; Incidence; Risk factors; Stomach neoplasms