Hughes, L.Williamson, E.Van Engeland, M.Jenkins, M.Giles, G.Hopper, J.Southey, M.Young, J.Buchanan, D.Walsh, M.Van den Brandt, P.Alexandra Goldbohm, R.Weijenberg, M.English, D.2014-11-272014-11-272012International Journal of Epidemiology, 2012; 41(4):1060-10720300-57711464-3685http://hdl.handle.net/2440/87657BACKGROUND: How body size influences risk of molecular subtypes of colorectal cancer (CRC) is unclear. We investigated whether measures of anthropometry differentially influence risk of tumours according to BRAF c.1799T>A p.V600E mutation (BRAF) and microsatellite instability (MSI) status. METHODS: Data from The Netherlands Cohort Study (n = 120,852) and Melbourne Collaborative Cohort Study (n = 40,514) were pooled and included 734 and 717 colorectal cancer cases from each study, respectively. Hazard ratios (HRs) and 95% confidence intervals (CIs) for body mass index (BMI), waist measurement and height were calculated and compared for subtypes defined by BRAF mutation and MSI status, measured from archival tissue. RESULTS: Results were consistent between studies. When pooled, BMI modelled in 5 kg/m(2) increments was positively associated with BRAF wild-type (HR: 1.16, 95% CI: 1.08-1.26) and MS-stable tumours (HR: 1.15, 95% CI: 1.06-1.24). Waist measurement was also associated with BRAF wild-type (highest vs lowest quartile, HR: 1.59, 95% CI: 1.33-1.90) and MS-stable tumours (highest vs lowest quartile HR: 1.68, 95% CI: 1.31-2.15). The HRs for BRAF mutation tumours and MSI tumours were smaller and non-significant, but differences between the HRs by tumour subtypes were not significant. Height, modelled per 5-cm increase, was positively associated with BRAF wild-type and BRAF mutation tumours, but the HR was greater for tumours with a BRAF mutation than BRAF wild-type (HR: 1.23, 95% CI: 1.11-1.37, P(heterogeneity) = 0.03). Similar associations were observed with respect to height and MSI tumours (HR: 1.26, 95% CI: 1.13-1.40, P(heterogeneity) = 0.02). CONCLUSIONS: Generally, overweight increases the risk of CRC. Taller individuals have an increased risk of developing a tumour with a BRAF mutation or MSI.en© The Author 2012; all rights reserved.Colorectal neoplasms; BRAF; microsatellite instability; body mass index; waist circumference; height; cohort studyJournal article003001202810.1093/ije/dys0550003082322000242-s2.0-84864607258143941Young, J. [0000-0002-1514-1522]