title: A Comprehensive Model of Colorectal Cancer by Risk Factor Status and Subsite Using Data From the Nurses' Health Study.
abstract: We expanded and updated our colon cancer risk model to evaluate colorectal cancer (CRC) and whether subsite-specific risk models are warranted. Using data from 1980-2010 for 90,286 women enrolled in the Nurses' Health Study, we performed competing-risks regression and tests for subsite heterogeneity (proximal colon: n = 821; distal colon: n = 521; rectum: n = 376). Risk factors for CRC were consistent with those in our colon cancer model. Processed meat consumption was associated with a higher risk of distal (hazard ratio (HR) = 1.45; P = 0.02) but not proximal (HR = 0.95; P = 0.72) colon cancer. Smoking was associated with both colon (HR = 1.21) and rectal (HR = 1.27) cancer and was more strongly associated with proximal (HR = 1.31) than with distal (HR = 1.04) colon cancer (P = 0.029). We observed a significant trend of cancer risk for smoking in subsites from the cecum (HR = 1.41) to the proximal colon (excluding the cecum; HR = 1.27) to the distal colon (HR = 1.04; P for trend = 0.040). The C statistics for colorectal (C = 0.607), colon (C = 0.603), and rectal (C = 0.639) cancer were similar, although C was slightly higher for rectal cancer. Despite evidence for site-specific differences for several risk factors, overall our findings support the application of risk prediction models for colon cancer to CRC.
authors.forename: Esther K
authors.initials: EK
authors.lastname: Wei
authors.forename: Graham A
authors.initials: GA
authors.lastname: Colditz
authors.forename: Edward L
authors.initials: EL
authors.lastname: Giovannucci
authors.forename: Kana
authors.initials: K
authors.lastname: Wu
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Glynn
authors.forename: Charles S
authors.initials: CS
authors.lastname: Fuchs
authors.forename: Meir
authors.initials: M
authors.lastname: Stampfer
authors.forename: Walter
authors.initials: W
authors.lastname: Willett
authors.forename: Shuji
authors.initials: S
authors.lastname: Ogino
authors.forename: Bernard
authors.initials: B
authors.lastname: Rosner
mesh_terms: D000328:Adult; D000368:Aged; D000428:Alcohol Drinking; D015179:Colorectal Neoplasms / Q000453:epidemiology / Q000209:etiology* / Q000401:mortality; D004032:Diet; D015444:Exercise; D005260:Female; D006801:Humans; D015994:Incidence; D008460:Meat / Q000009:adverse effects; D008875:Middle Aged; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012004:Rectal Neoplasms / Q000453:epidemiology / Q000209:etiology; D018570:Risk Assessment; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects; D011795:Surveys and Questionnaires; D016019:Survival Analysis
keywords: colorectal cancer; incidence; rectal cancer; risk; risk factors; risk prediction model; women