title: Splenectomy and increased subsequent cancer risk: a nationwide population-based cohort study.
abstract: BACKGROUND
  Splenectomy has been suggested to have an impact on immunological function, and subsequent development of cancer has been recognized as a possible adverse effect of splenectomy. This study evaluated the possible association between splenectomy and malignancy in Taiwan.
  
  
  METHODS
  A cohort study consisted of including 2,603 patients with nontraumatic and 2,295 patients with traumatic splenectomy, and then randomly frequency matched with 4 participants without splenectomy. The Cox proportional hazard regression analysis was conducted to estimate the influence of splenectomy on cancer risk.
  
  
  RESULTS
  Both nontraumatic and traumatic splenectomy had a significantly higher risk for overall cancer development (adjusted hazard ratios are 2.64 and 1.29 for nontraumatic and traumatic reasons, respectively). After adjusting for age, sex, and comorbidities, patients with splenectomy were associated with significantly higher risks for developing certain gastrointestinal tract cancers, other head and neck cancers, and hematological malignancies, and the phenomenon is more prominent in nontraumatic splenectomy group.
  
  
  CONCLUSIONS
  This nationwide population-based study found that people with splenectomy have higher risks of developing overall cancer, as well as certain site-specific cancers, especially for patients with nontraumatic reasons.
authors.affiliation: Department of Radiation Oncology, Zuoying Branch of Kaohsiung Armed Forces General Hospital, Kaohsiung, Taiwan.
authors.forename: Li-Min
authors.initials: LM
authors.lastname: Sun
authors.affiliation: Management Office for Health Data, China Medical University Hospital, Taichung, Taiwan; College of Medicine, China Medical University, Taichung, Taiwan.
authors.forename: Hsuan-Ju
authors.initials: HJ
authors.lastname: Chen
authors.affiliation: Department of Surgery, Organ Transplantation Center, China Medical University Hospital, Taichung, Taiwan; Graduate Institute of Clinical Medical Science and School of Medicine, College of Medicine, China Medical University, Taichung, Taiwan.
authors.forename: Long-Bin
authors.initials: LB
authors.lastname: Jeng
authors.affiliation: Graduate Institute of Biostatistics, College of Management, China Medical University, Taichung, Taiwan; Department of Healthcare Administration, College of Health Science, Asia University, Taichung, Taiwan.
authors.forename: Tsai-Chung
authors.initials: TC
authors.lastname: Li
authors.affiliation: Graduate Institute of Clinical Medical Science and School of Medicine, College of Medicine, China Medical University, Taichung, Taiwan; Trauma and Emergency Center, China Medical University Hospital, Taichung, Taiwan.
authors.forename: Shih-Chi
authors.initials: SC
authors.lastname: Wu
authors.affiliation: Graduate Institute of Clinical Medical Science and School of Medicine, College of Medicine, China Medical University, Taichung, Taiwan; Department of Nuclear Medicine and PET Center, China Medical University Hospital, Taichung, Taiwan. Electronic address: d10040@mail.cmuh.org.tw.
authors.forename: Chia-Hung
authors.initials: CH
authors.lastname: Kao
mesh_terms: D000328:Adult; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000453:epidemiology* / Q000209:etiology*; D012189:Retrospective Studies; D018570:Risk Assessment; D013154:Spleen / Q000293:injuries; D013156:Splenectomy / Q000009:adverse effects*; D013624:Taiwan; D055815:Young Adult
keywords: Cox proportional hazard regression analysis; Malignancy; Population-based cohort study; Splenectomy; The National Health Insurance system