Do alcoholic beverages, obesity and other nutritional factors modify the risk of familial colorectal cancer?
Résumé
Background:
Familial cancers could result from inherited genes (either penetrant inherited syndromes or low-penetrance genes), environmental/lifestyle factors shared within the family especially between first degree relatives, or some combination of these. Individuals with family history of colorectal cancer are at higher risk of colorectal cancer than the general population. Until now, guidelines for familial colorectal cancer risk have only pointed at early diagnosis efforts via screening tests and surveillance, and payed scarce or no attention to lowering exposure to modifiable risk factors, notably nutritional factors.
Methods:
We conducted a systematic review of epidemiological studies investigating the associations between nutritional factors, family history of colorectal cancer, and colorectal cancer risk. From the 5312 abstracts identified until December 2016, 184 full text articles were examined for eligibility. Finally, 31 studies (21 case-control, 9 cohort and 1 interventional studies) met inclusion criteria and were analyzed.
Results:
Mainly, the combinations of family history of colorectal cancer and higher consumptions of alcoholic beverages, red or processed meat, or overweight/obesity increase the risk of colorectal cancer. Consistently, a strong increase is observed with the combinations of family history of colorectal cancer and unhealthy dietary patterns/lifestyles. Statistically significant interactions between these nutritional factors, family history of colorectal cancer and colorectal cancer risk are
reported. This suggests that, in subjects with family history of colorectal cancer who are exposed to multiple nutritional risk factors, the probability that one (or several) risk factor(s) interact/act in synergy with one (or several) specific inherited genetic polymorphism(s) or single mutation(s) is very high.
Conclusions:
For the first time, our findings highlight that addressing high consumption of alcoholic beverages, red
or processed meat, and overweight/obesity, and more largely the exposure to multiple unhealthy dietary/nutritional behaviors could offer new perspectives of prevention to individuals with family history of colorectal cancer. A better information of these patients and of health professionals on these nutritional modifiable risk factors is recommended