title: On the role of aging in carcinogenesis.
abstract: BACKGROUND
  Previously we identified the age at half-total incidence (Age 1/2) for a variety of tumors. In this paper, we compare the Age 1/2 with the age- standardized incidence rate (ASR) in populations that differ a) genetically and environmentally and b) genetically but not environmentally.
  
  
  METHODS
  From 1990-era data, we calculated 95% confidence limits about mean values for Age 1/2 and ASR for cancers of the stomach, colon, rectum, lung, female breast, corpus uterus, ovary, testis and prostate.
  
  
  RESULTS
  In populations that differed genetically and environmentally as well as those that differed genetically but not environmentally, we observed large variations in ASR, with little or no variation in Age 1/2.
  
  
  CONCLUSIONS
  The determinants of ASR are distinct from the determinants of Age 1/2 and likely to be genes that can vary between tissues of tumor origin but are common to all people.
authors.affiliation: Department of Biology, University of Hartford, West Harford, CT 06117, USA.
authors.forename: S
authors.initials: S
authors.lastname: Leipold
authors.forename: A A
authors.initials: AA
authors.lastname: Madeyanda
authors.forename: D
authors.initials: D
authors.lastname: Dix
mesh_terms: D000367:Age Factors; D000375:Aging / Q000235:genetics*; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D009369:Neoplasms / Q000453:epidemiology* / Q000235:genetics*