title: Conditional survival for pediatric and adolescent patients with cancer: Implications for survivorship care.
abstract: OBJECTIVE
  Few studies have evaluated conditional survival (probability of surviving y years given patients have already survived x years) for pediatric/adolescent patients diagnosed with cancer. To provide more accurate information on ongoing survival, we evaluate conditional survival for pediatric and adolescent patients with cancer.
  
  
  METHODS
  The statewide Utah Cancer Registry identified 3344 patients born in Utah diagnosed with cancer at ages 0-21 years, from 1973 to 2009. The Utah Population Database provided demographic information. We estimated five-year conditional survival at diagnosis, and one and three years after diagnosis, by risk factors such as cancer type, sex, diagnosis age and treatment era (1973-1994 vs. 1995-2009).
  
  
  RESULTS
  Conditional survival estimates at one (85.1%, 95% CI: 83.7-86.5) and three years (92.9%, 95% CI: 91.8-93.9) after diagnosis were significantly higher than survival at diagnosis (77.2%, 95% CI: 75.6-78.9), although results varied by cancer type and initial prognosis. Diagnosis age affected survival for cancers where age is a risk factor. For example, five-year survival at one year after diagnosis was higher for younger (≤ 18 months of age) patients compared to older (>18 months) patients with neuroblastoma (95.4%, 95% CI: 90.9-99.9 vs. 56.8%, 95% CI: 41.8-71.7, p<0.001). Conditional survival improved over time for many cancers. Minimal differences were observed by sex.
  
  
  CONCLUSIONS
  Substantial improvements were observed in conditional survival at one and three years after diagnosis compared with survival at diagnosis. Several risk factors affected these outcomes. Clearer understandings of survival will help in administering effective survivorship care and decreasing prognosis-related anxiety/stress for patients and families.
authors.affiliation: Preventive Medicine and Community Health, University of Texas Medical Branch, United States. Electronic address: sakaul@UTMB.EDU.
authors.forename: Sapna
authors.initials: S
authors.lastname: Kaul
authors.affiliation: Pediatric Hematology/Oncology and Huntsman Cancer Institute, University of Utah, United States. Electronic address: Anne.Kirchhoff@hci.utah.edu.
authors.forename: Anne C
authors.initials: AC
authors.lastname: Kirchhoff
authors.affiliation: Huntsman Cancer Institute, University of Utah, United States. Electronic address: Kenneth.Boucher@hci.utah.edu.
authors.forename: Kenneth M
authors.initials: KM
authors.lastname: Boucher
authors.affiliation: Children's Hospital Los Angeles, University of Southern California, United States. Electronic address: adietz@chla.usc.edu.
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Dietz
mesh_terms: D000293:Adolescent; D001007:Anxiety / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009369:Neoplasms / Q000401:mortality*; D009447:Neuroblastoma / Q000401:mortality*; D011379:Prognosis; D012307:Risk Factors; D016019:Survival Analysis; D015996:Survival Rate; D055815:Young Adult
keywords: Adolescent cancer; Conditional survival; Pediatric cancer