title: An individualized conditional survival calculator for patients with rectal cancer.
abstract: BACKGROUND
  Conditional survival estimates account for time survived since diagnosis to provide prognostic information for long-term cancer survivors. For rectal cancer, stage-related treatment (eg, neoadjuvant radiotherapy) affects pathologic stage and therefore stage-associated survival estimates.
  
  
  OBJECTIVE
  The aim of this study is to estimate conditional survival for patients who have rectal cancer and to develop an interactive calculator to use for individualized patient counseling.
  
  
  METHODS
  Patients with rectal adenocarcinoma were identified by using the Surveillance Epidemiology and End Results registry (1988-2002, N = 22,610).
  
  
  METHODS
  Cox regression models were developed to determine adjusted survival estimates (years 1-10) and used to calculate 5-year adjusted conditional survival. Models were built separately for no radiotherapy, preoperative radiotherapy, postoperative radiotherapy, and patients with stage IV disease. Covariates included age, sex, race, tumor grade, and type of surgery. An Internet-based conditional survival calculator was developed.
  
  
  RESULTS
  Radiotherapy was given to 42.6% of patients (14.1% preoperative, 28.4% postoperative). Significant improvements in 5-year conditional survival were observed for all stages, with the exception of stage I because of the initial high survival probability at diagnosis. Patients with advanced stage had the greatest improvements in conditional survival, with 5-year absolute increases of 33% (stage IIIC) and 54% (IV). Other factors associated with conditional survival included sequence of radiotherapy and surgery, age, race, and tumor grade. The Internet-based conditional survival calculator can be accessed at www.mdanderson.org/rectalcalculator.
  
  
  CONCLUSIONS
  The data source used does not include information on chemotherapy treatment, change in staging after neoadjuvant treatment, or patient comorbidities.
  
  
  CONCLUSIONS
  Conditional survival estimates improve over 5 years in patients who have rectal cancer; the greatest improvements are observed among patients with advanced stage disease. The conditional survival calculator is an individualized decision support tool that informs patients, who must make non-treatment-related life decisions, and their clinicians planning follow-up and surveillance.
authors.affiliation: Department of Surgical Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas 77230-1402, USA.
authors.forename: Tawnya L
authors.initials: TL
authors.lastname: Bowles
authors.forename: Chung-Yuan
authors.initials: CY
authors.lastname: Hu
authors.forename: Nancy Y
authors.initials: NY
authors.lastname: You
authors.forename: John M
authors.initials: JM
authors.lastname: Skibber
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Rodriguez-Bigas
authors.forename: George J
authors.initials: GJ
authors.lastname: Chang
mesh_terms: D000230:Adenocarcinoma / Q000401:mortality / Q000473:pathology / Q000628:therapy; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D015331:Cohort Studies; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008017:Life Expectancy; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009367:Neoplasm Staging; D011379:Prognosis; D016016:Proportional Hazards Models; D012004:Rectal Neoplasms / Q000401:mortality / Q000473:pathology / Q000628:therapy; D012007:Rectum / Q000601:surgery*; D018426:SEER Program; D012737:Sex Factors