title: Relationships of obesity and diabetes mellitus to other primary cancers in surgically treated gastric cancer patients.
abstract: BACKGROUND
  Other primary cancers (OPC) have been reported in gastric cancer (GC) patients. Recent studies have shown relationships of obesity and diabetes mellitus to cancer development in several organs. The purpose of this study was to investigate the relationships of obesity and diabetes mellitus (DM) to the prevalence of OPC in GC patients.
  
  
  METHODS
  We reviewed 435 GC patients who were treated surgically and followed their outcomes after surgery. Patients with body mass index (BMI) ≥ 25 kg/m(2) were defined as obese. Fasting plasma glucose (FPG) and HbA1c levels were examined before surgery.
  
  
  RESULTS
  OPC was observed in 109 GC patients (25.1%): 40 (9.2%) with synchronous OPC and 76 (18.2%) with metachronous OPC. The most common OPC was colorectal cancer (22.8%). OPC was frequently observed in patients with DM (p = 0.0022), and DM was an independent risk factor for the occurrence of OPC (odds ratio, 2.215; 95% confidence interval, 1.2007-4.0850; p = 0.011). Synchronous OPC was frequently observed in patients with obesity (p = 0.025), and obesity was an independent risk factor for the occurrence of synchronous OPC (odds ratio, 2.354; 95% confidence interval, 1.1246-4.9279; p = 0.023). Metachronous OPC was frequently observed in patients with DM (p = 0.0071), and DM was an independent risk factor for the occurrence of OPC (odds ratio, 2.680; 95% confidence interval, 1.0291-6.9780; p = 0.044).
  
  
  CONCLUSIONS
  There is a need to be aware of the possibility of OPC in GC patients with DM/obesity. They should undergo intensive screening for OPC before and after gastrectomy.
authors.affiliation: Department of Surgery, Shinshu University School of Medicine, Asahi 3-1-1, Matsumoto 390-8621, Japan. Electronic address: takeuchi_daichan@yahoo.co.jp.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Takeuchi
authors.affiliation: Department of Surgery, Shinshu University School of Medicine, Asahi 3-1-1, Matsumoto 390-8621, Japan.
authors.forename: Naohiko
authors.initials: N
authors.lastname: Koide
authors.affiliation: Department of Surgery, Shinshu University School of Medicine, Asahi 3-1-1, Matsumoto 390-8621, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Komatsu
authors.affiliation: Department of Surgery, Shinshu University School of Medicine, Asahi 3-1-1, Matsumoto 390-8621, Japan.
authors.forename: Motohiro
authors.initials: M
authors.lastname: Okumura
authors.affiliation: Department of Surgery, Shinshu University School of Medicine, Asahi 3-1-1, Matsumoto 390-8621, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Suzuki
authors.affiliation: Department of Surgery, Shinshu University School of Medicine, Asahi 3-1-1, Matsumoto 390-8621, Japan.
authors.forename: Shinichi
authors.initials: S
authors.lastname: Miyagawa
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015992:Body Mass Index; D015179:Colorectal Neoplasms / Q000453:epidemiology; D003924:Diabetes Mellitus, Type 2 / Q000453:epidemiology*; D055088:Early Detection of Cancer; D005260:Female; D005743:Gastrectomy; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009378:Neoplasms, Multiple Primary / Q000175:diagnosis / Q000453:epidemiology*; D016609:Neoplasms, Second Primary / Q000175:diagnosis / Q000453:epidemiology*; D009765:Obesity / Q000453:epidemiology*; D015995:Prevalence; D012307:Risk Factors; D013274:Stomach Neoplasms / Q000453:epidemiology* / Q000601:surgery
keywords: Body mass index; Diabetes mellitus; Gastric cancer; Obesity; Other primary cancer