title: Cancer risk among patients with systemic sclerosis: a nationwide population study in Taiwan.
abstract: OBJECTIVE
  Systemic sclerosis (SSc) has been associated with high cancer risk. We compared the cancer risk among SSc patients with that among the general Taiwanese population.
  
  
  METHODS
  The catastrophic illness registry of the Taiwan National Health Insurance Research Dataset (NHIRD) was used to identify patients diagnosed with SSc and cancer in Taiwan during 1996-2008. The standardized incidence ratio (SIR) for cancer was calculated, and mortality was ascertained using the data from the National Death Registry.
  
  
  RESULTS
  Data analysis revealed that 2053 (472 men, 1581 women) Taiwanese individuals were diagnosed with SSc during the study period and 83 (30 men, 53 women) had cancer. The incidence of cancer was 6.9/1000 person-years. The most common cancer sites in male SSc patients were the lung (n = 10), oral cavity and pharynx (n = 8), and gastrointestinal tract (n = 4), and those in female patients were the breast (n = 11), lungs (n = 11), and blood (n = 6). Compared to the Taiwanese population of 1996, the all-cancer SIR for SSc was 1.63 [95% confidence interval (CI) 1.31-2.01]. Cancer risk was elevated for cancers of the lung (SIR 4.20), oral cavity and pharynx (SIR 3.67), and blood (SIR 3.50). A cancer diagnosis in SSc patients was associated with a hazard ratio (HR) of 2.15 (95% CI 1.30-3.53). Among cancer patients, a diagnosis of SSc was not associated with increased mortality.
  
  
  CONCLUSIONS
  SSc patients are at high risk of developing cancer, especially of the lung, oral cavity and pharynx, and blood.
authors.affiliation: Graduate Institute of Clinical Medical Sciences, Chang Gung University, Taoyuan, Taiwan.
authors.forename: C-F
authors.initials: CF
authors.lastname: Kuo
authors.forename: S-F
authors.initials: SF
authors.lastname: Luo
authors.forename: K-H
authors.initials: KH
authors.lastname: Yu
authors.forename: I-J
authors.initials: IJ
authors.lastname: Chou
authors.forename: W-Y
authors.initials: WY
authors.lastname: Tseng
authors.forename: H-C
authors.initials: HC
authors.lastname: Chang
authors.forename: Y-F
authors.initials: YF
authors.lastname: Fang
authors.forename: M-J
authors.initials: MJ
authors.lastname: Chiou
authors.forename: L-C
authors.initials: LC
authors.lastname: See
mesh_terms: D000328:Adult; D005260:Female; D019337:Hematologic Neoplasms / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D008175:Lung Neoplasms / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000453:epidemiology; D009369:Neoplasms / Q000453:epidemiology*; D010610:Pharyngeal Neoplasms / Q000453:epidemiology; D012042:Registries; D012307:Risk Factors; D012595:Scleroderma, Systemic / Q000453:epidemiology*; D013624:Taiwan / Q000453:epidemiology