Associations Of Red And Processed Meat With Survival After Colorectal Cancer And Differences According To Timing Of Dietary Assessment

Prudence CARR, German Cancer Research Center, Germany
JANSEN L. 1 , WALTER V. 1 , KLOOR M. 2 , ROTH W. 3,4 , BL─KER H. 5 , CHANG-CLAUDE J. 6 , BRENNER H. 1,7,8 , HOFFMEISTER M. 1

1 Division of Clinical Epidemiology and Aging Research, German Cancer Research Center, Heidelberg, Germany
2 Department of Applied Tumor Biology, Institute of Pathology, Heidelberg University Hospital, Germany
3 Department of Pathology, Institute of Pathology, Heidelberg University Hospital, Germany
4 Unit of Molecular Tumor Pathology, German Cancer Research Center, Heidelberg, Germany
5 Institute of Pathology, CharitÚ University Medicine, Berlin, Germany
6 Division of Cancer Epidemiology, German Cancer Research Center, Heidelberg, Germany
7 Division of Preventive Oncology, German Cancer Research Center, Heidelberg, Germany
8 German Cancer Consortium (DKTK), German Cancer Research Center, Heidelberg, Germany

Purpose: Little is known about the prognostic impact of red and processed meat intake or about changes in consumption after a diagnosis of colorectal cancer (CRC). We investigated associations of baseline red and processed meat with survival outcomes and explored changes in intake among CRC survivors five years after diagnosis.
Methods: 3122 patients diagnosed with CRC between 2003-2010 were followed for a median time of 4.8 years (DACHS study). Patients provided information on diet and other factors in standardized questionnaires at baseline and at 5-year follow-up. Cox proportional hazards regression models were used to estimate HRs and 95% CIs.
Results: Among stage I-III CRC patients, baseline red and processed meat intake was not associated with overall (>1 time/day vs <1 time/day, HR 0.85; 95% CI, 0.67,1.09), CRC-specific (HR 0.83; 95% CI, 0.61,1.14), CVD-specific (HR 0.92, 95% CI, 0.51,1.68), non-CRC-specific (HR 0.88; 95% CI, 0.59,1.30) and recurrence free (HR 1.03; 95% CI, 0.80,1.33) survival; results among stage IV patients were comparable. An association with worse overall survival was found among patients with KRAS-mutated CRC (HR 1.99; 95% CI, 1.10, 3.56), but not with MSI or CIMP positivity. A much lower proportion of survivors reported daily consumption of red and processed meat at 5-year follow-up than at baseline (concordance rate 39%, kappa-value 0.10; 95% CI 0.07, 0.13).
Conclusions: Our findings suggest that baseline red and processed meat intake is not associated with poorer survival among patients with CRC. The potential interaction with KRAS mutation status warrants further evaluation. Major changes in consumption measured at the 5-year follow-up may have had an impact on our survival estimates. 
Funding source: German Research Council (BR 1704/6-1, BR 1704/6-3, BR 1704/6-4, CH 117/1-1, HO 5117/2-1), German Federal Ministry of Education and Research (01KH0404, 01ER0814)​, the Interdisciplinary Research Program of the National Center for Tumor Diseases, Germany.