title: Relative survival is an adequate estimate of cancer-specific survival: baseline mortality-adjusted 10-year survival of 771 rectal cancer patients.
abstract: BACKGROUND
  The objective of the present investigation is to assess the baseline mortality-adjusted 10-year survival of rectal cancer patients.
  
  
  METHODS
  Ten-year survival was analyzed in 771 consecutive American Joint Committee on Cancer (AJCC) stage I-IV rectal cancer patients undergoing open resection between 1991 and 2008 using risk-adjusted Cox proportional hazard regression models adjusting for population-based baseline mortality.
  
  
  RESULTS
  The median follow-up of patients alive was 8.8 years. The 10-year relative, overall, and cancer-specific survival were 66.5% [95% confidence interval (CI) 61.3-72.1], 48.7% (95% CI 44.9-52.8), and 66.4% (95% CI 62.5-70.5), respectively. In the entire patient sample (stage I-IV) 47.3% and in patients with stage I-III 33.6 % of all deaths were related to rectal cancer during the 10-year period. For patients with AJCC stage I rectal cancer, the 10-year overall survival was 96% and did not significantly differ from an average population after matching for gender, age, and calendar year (p = 0.151). For the more advanced tumor stages, however, survival was significantly impaired (p < 0.001).
  
  
  CONCLUSIONS
  Retrospective investigations of survival after rectal cancer resection should adjust for baseline mortality because a large fraction of deaths is not cancer related. Stage I rectal cancer patients, compared to patients with more advanced disease stages, have a relative survival close to 100% and can thus be considered cured. Using this relative-survival approach, the real public health burden caused by rectal cancer can reliably be analyzed and reported.
authors.affiliation: Department of Surgery, Kantonsspital St. Gallen, St. Gallen, Switzerland, ignazio.tarantino@kssg.ch.
authors.forename: Ignazio
authors.initials: I
authors.lastname: Tarantino
authors.forename: Philipp
authors.initials: P
authors.lastname: Achermann
authors.forename: Ulrich
authors.initials: U
authors.lastname: Güller
authors.forename: Alexis
authors.initials: A
authors.lastname: Ulrich
authors.forename: Bruno M
authors.initials: BM
authors.lastname: Schmied
authors.forename: Daniel
authors.initials: D
authors.lastname: Horber
authors.forename: Thomas
authors.initials: T
authors.lastname: Cerny
authors.forename: Zeno
authors.initials: Z
authors.lastname: Stanga
authors.forename: Rene
authors.initials: R
authors.lastname: Warschkow
mesh_terms: D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D009367:Neoplasm Staging; D011379:Prognosis; D016016:Proportional Hazards Models; D012004:Rectal Neoplasms / Q000401:mortality* / Q000473:pathology / Q000601:surgery; D012189:Retrospective Studies; D012307:Risk Factors; D015996:Survival Rate; D013997:Time Factors