title: Tumor location and patient characteristics of colon and rectal adenocarcinomas in relation to survival and TNM classes.
abstract: BACKGROUND
  Old age at diagnosis is associated with poor survival in colorectal cancer (CRC) for unknown reasons. Recent data show that colonoscopy is efficient in preventing left-sided cancers only. We examine the association of Tumor Node Metastasis (TNM) classes with diagnostic age and patient characteristics.
  
  
  METHODS
  The Swedish Family-Cancer Database has data on TNM classes on 6,105 CRC adenocarcinoma patients. Ordinal logistic regression analysis was performed to model tumor characteristics according to age at diagnosis, tumor localization, gender, socioeconomic status, medical region and family history. The results were compared to results from survival analysis.
  
  
  RESULTS
  The only parameters systematically associated with TNM classes were age and tumor localization. Young age at diagnosis was a risk factor for aggressive CRC, according to stage, N and M with odds ratios (ORs) ranging from 1.80 to 1.93 for diagnosis before age 50 years compared to diagnosis at 80+ years. All tumor characteristics, particularly T, were worse for colon compared to rectal tumors. Right-sided tumors showed worse characteristics for all classifiers but M. The survival analysis on patients diagnosed since 2000 showed a hazard ratio of 0.55 for diagnosis before age 50 years compared to diagnosis at over 80 years and a modestly better prognosis for left-sided compared to right-sided tumors.
  
  
  CONCLUSIONS
  The results showed systematically more aggressive tumors in young compared to old patients. The poorer survival of old patients in colon cancer was not related to the available tumor characteristics. However, these partially agreed with the limited colonoscopic success with right-sided tumors.
authors.affiliation: Division of Molecular Genetic Epidemiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 580, D-69120 Heidelberg, Germany. k.hemminki@dkfz.de
authors.forename: Kari
authors.initials: K
authors.lastname: Hemminki
authors.forename: Irene
authors.initials: I
authors.lastname: Santi
authors.forename: Marianne
authors.initials: M
authors.lastname: Weires
authors.forename: Hauke
authors.initials: H
authors.lastname: Thomsen
authors.forename: Jan
authors.initials: J
authors.lastname: Sundquist
authors.forename: Justo Lorenzo
authors.initials: JL
authors.lastname: Bermejo
mesh_terms: D000230:Adenocarcinoma / Q000401:mortality* / Q000473:pathology*; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000401:mortality* / Q000473:pathology*; D005260:Female; D006801:Humans; D016015:Logistic Models; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D016017:Odds Ratio; D011379:Prognosis; D012042:Registries; D018570:Risk Assessment; D012307:Risk Factors; D016019:Survival Analysis; D013548:Sweden / Q000453:epidemiology; D013997:Time Factors