title: Risk factors for young-onset colorectal cancer.
abstract: OBJECTIVE
  We investigated risk factors for colorectal cancer in early-onset cancers, to provide quantitative estimates for major selected risk factors.
  
  
  METHODS
  We analyzed data from three Italian and Swiss case-control studies conducted between 1985 and 2009, including 329 colorectal cancer cases and 1,361 controls aged ≤45 years. We computed odds ratios (ORs) from unconditional logistic regression models, adjusted for major confounding factors.
  
  
  RESULTS
  The OR of young-onset colorectal cancer was 4.50 for family history of colorectal cancer in first-degree relatives, the association being higher in subjects with affected siblings (OR 11.68) than parents (OR 3.75). The ORs of young-onset colorectal cancer were 1.56 for ≥14 drinks/week of alcohol, 1.56 for the highest tertile of processed meat, 0.40 for vegetables, 0.75 for fruit, and 0.78 for fish intake. Among micronutrients, the ORs were 0.52 for β-carotene, 0.68 for vitamin C, 0.38 for vitamin E, and 0.59 for folate. No significant associations emerged for physical activity, overweight, and diabetes.
  
  
  CONCLUSIONS
  This study-the largest on young-onset colorectal cancer-confirms that several recognized risk factors for colorectal cancer are also relevant determinants of young-onset colorectal cancer. Family history of colorectal cancer in particular is a stronger risk factor in young subjects, as compared to middle age and elderly ones.
authors.affiliation: Department of Epidemiology, Istituto di Ricerche Farmacologiche Mario Negri, Via Giuseppe La Masa 19, 20156, Milan, Italy.
authors.forename: Valentina
authors.initials: V
authors.lastname: Rosato
authors.forename: Cristina
authors.initials: C
authors.lastname: Bosetti
authors.forename: Fabio
authors.initials: F
authors.lastname: Levi
authors.forename: Jerry
authors.initials: J
authors.lastname: Polesel
authors.forename: Antonella
authors.initials: A
authors.lastname: Zucchetto
authors.forename: Eva
authors.initials: E
authors.lastname: Negri
authors.forename: Carlo
authors.initials: C
authors.lastname: La Vecchia
mesh_terms: D000328:Adult; D017668:Age of Onset; D016022:Case-Control Studies; D015179:Colorectal Neoplasms / Q000453:epidemiology*; D004032:Diet; D005260:Female; D006801:Humans; D007558:Italy / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D013557:Switzerland / Q000453:epidemiology