title: The prognostic significance of age in operated and non-operated colorectal cancer.
abstract: BACKGROUND
  The prognostic significance of age in colorectal cancer remains controversial. Our purpose was to determine the impact of age at diagnosis on cause- specific survival and overall survival in patients with colorectal cancer.
  
  
  METHODS
  Using Surveillance, Epidemiology, and End Results (SEER) population-based data, we identified 226,430 patients with colorectal cancer diagnosed between 1996 and 2005. Patients were separated into 10-year age groups. Five-year cancer cause-specific survival and overall survival data were obtained. Kaplan-Meier methods were adopted and multivariable Cox regression models were built for the analysis of long-term survival outcomes and risk factors.
  
  
  RESULTS
  In the operated group, those aged 51-60 had the best prognosis with 5-year cause-specific survival of 72.3% and 5-year overall survival of 68.3%.In the non-operated group, those of young age 15-30 had the best prognosis with 5-year cause-specific survival of 21.2% and 5-year overall survival of 18.2%, and there was continued worsening in cause-specific survival and overall survival with increasing age, except for a small increase in the 51-60 age group (P < 0.001). Multivariable analysis demonstrated a statistically significant disadvantage in cause-specific survival in patients older than 60 (P < 0.001), but the difference between the 51-60 age group and the younger age group (15-30, 31-40, 41-50) wasn't statistically significant (P > 0.05) in both operated and non-operated patients.
  
  
  CONCLUSIONS
  There was no apparent difference in survival in colorectal cancer patients 60 and younger, but in those older than 60 years, there was worsening in overall survival and cause-specific survival in both operated and non-operated patients.
authors.affiliation: Department of Oncology, The Second Clinical School of Yangzhou University (Yangzhou NO.1 People's Hospital), Mid Hanjiang Road, Yangzhou, 225009, Jiangsu Province, People's Republic of China. lijyz@sohu.com.|Research Center of Cancer Prevention and Treatment, Medical College of Yangzhou University, Number 11, Huaihai Road, Yangzhou, 225001, Jiangsu Province, People's Republic of China. lijyz@sohu.com.
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Oncology, The Second Clinical School of Yangzhou University (Yangzhou NO.1 People's Hospital), Mid Hanjiang Road, Yangzhou, 225009, Jiangsu Province, People's Republic of China. 26574021@qq.com.
authors.forename: Zhu
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Department of Oncology, The Second Clinical School of Yangzhou University (Yangzhou NO.1 People's Hospital), Mid Hanjiang Road, Yangzhou, 225009, Jiangsu Province, People's Republic of China. 1499733865@qq.com.
authors.forename: Xin
authors.initials: X
authors.lastname: Yuan
authors.affiliation: Research Center of Cancer Prevention and Treatment, Medical College of Yangzhou University, Number 11, Huaihai Road, Yangzhou, 225001, Jiangsu Province, People's Republic of China. yxyxlc@aliyun.com.
authors.forename: Lichun
authors.initials: L
authors.lastname: Xu
authors.affiliation: Department of Oncology, The Second Clinical School of Yangzhou University (Yangzhou NO.1 People's Hospital), Mid Hanjiang Road, Yangzhou, 225009, Jiangsu Province, People's Republic of China. tongjiandong@csco.org.cn.
authors.forename: Jiandong
authors.initials: J
authors.lastname: Tong
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D015179:Colorectal Neoplasms / Q000401:mortality* / Q000473:pathology* / Q000601:surgery; D006801:Humans; D008875:Middle Aged; D011379:Prognosis; D016016:Proportional Hazards Models; D018426:SEER Program; D016019:Survival Analysis; D055815:Young Adult