Pre-diagnostic meat and fibre intakes in relation to colorectal cancer survival in the European Prospective Investigation into Cancer and Nutrition.

Improvements in colorectal cancer (CRC) detection and treatment have led to greater numbers of CRC survivors, for whom there is limited evidence on which to provide dietary guidelines to improve survival outcomes. Higher intake of red and processed meat and lower intake of fibre are associated with greater risk of developing CRC, but there is limited evidence regarding associations with survival after CRC diagnosis. Among 3789 CRC cases in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort, pre-diagnostic consumption of red meat, processed meat, poultry and dietary fibre was examined in relation to CRC-specific mortality (n 1008) and all-cause mortality (n 1262) using multivariable Cox regression models, adjusted for CRC risk factors. Pre-diagnostic red meat, processed meat or fibre intakes (defined as quartiles and continuous grams per day) were not associated with CRC-specific or all-cause mortality among CRC survivors; however, a marginal trend across quartiles of processed meat in relation to CRC mortality was detected (P 0·053). Pre-diagnostic poultry intake was inversely associated with all-cause mortality among women (hazard ratio (HR)/20 g/d 0·92; 95 % CI 0·84, 1·00), but not among men (HR 1·00; 95 % CI 0·91, 1·09) (P for heterogeneity=0·10). Pre-diagnostic intake of red meat or fibre is not associated with CRC survival in the EPIC cohort. There is suggestive evidence of an association between poultry intake and all-cause mortality among female CRC survivors and between processed meat intake and CRC-specific mortality; however, further research using post-diagnostic dietary data is required to confirm this relationship.

Circulating biomarkers of one-carbon metabolism in relation to renal cell carcinoma incidence and survival.

BACKGROUND: The etiology of renal cell carcinoma (RCC) is only partially understood, but a metabolic component appears likely. We investigated biomarkers of one-carbon metabolism and RCC onset and survival. METHODS: The European Prospective Investigation into Cancer and Nutrition (EPIC) recruited 385747 participants with blood samples between 1992 and 2000, and this analysis included 556 RCC case-control pairs. A subsequent replication study included 144 case-control pairs nested within the Melbourne Collaborative Cohort Study (MCCS). Plasma concentrations of vitamin B2, vitamin B6, folate, vitamin B12, methionine and homocysteine were measured in prediagnostic samples and evaluated with respect to RCC risk using conditional and unconditional logistic regression models, and to all-cause mortality in RCC cases using Cox regression models. All statistical tests were two-sided. RESULTS: EPIC participants with higher plasma concentrations of vitamin B6 had lower risk of RCC, the odds ratio comparing the 4(th) and 1(st) quartiles (OR4vs1) being 0.40 95% confidence interval [CI] = 0.28 to 0.57, P trend < .001. We found similar results after adjusting for potential confounders (adjusted P trend < .001). In survival analysis, the hazard ratio for all-cause mortality in RCC cases when comparing the 4(th) and 1(st) quartiles (HR4vs1) of vitamin B6 was 0.57 (95% CI = 0.37 to 0.87, P trend < .001). Subsequent replication of these associations within the MCCS yielded very similar results for both RCC risk (OR4vs1 = 0.47, 95% CI = 0.23 to 0.99, P trend = .07) and all-cause mortality (HR4vs1 = 0.56, 95% CI = 0.27 to 1.17, P trend = .02). No association was evident for the other measured biomarkers. CONCLUSION: Study participants with higher circulating concentrations of vitamin B6 had lower risk of RCC and improved survival following diagnosis in two independent cohorts.