The effects of nutritional interventions on recurrence in survivors of colorectal adenomas and cancer: a systematic review of randomised controlled trials

TY - JOUR

T1 - The effects of nutritional interventions on recurrence in survivors of colorectal adenomas and cancer

T2 - a systematic review of randomised controlled trials

AU - van Dijk, M.

AU - Pot, G. K.

PY - 2016/1/13

Y1 - 2016/1/13

N2 - Background/Objectives:Nutrition and dietary supplementation may modulate outcomes in colorectal cancer (CRC) survivors. However, no recent systematic review has focused on randomised controlled trials (RCTs). The aim of this systematic review was to examine the effects of nutritional RCTs in survivors of colorectal adenomas and cancer.Subjects/Methods:Medline, Embase, Scopus, Web of Science and the Cochrane Library were searched to identify research between April 2006 and January 2014. The primary outcomes were colorectal adenoma and cancer recurrence. Each included study was assessed for risk of bias. A meta-analysis using a random-effects model was performed, in which two or more RCTs investigated the same dietary intervention.Results:Eight completed RCTs, all in colorectal adenoma survivors, were identified, with four investigating the effect of folic acid. A meta-analysis of the four folic acid RCTs showed no statistically significant effect of folic acid on colorectal adenoma recurrence (relative risks=0.93; 95% confidence interval: 0.69, 1.25). The impact of the remaining completed RCTs, investigating antioxidant supplementation, green tea extract, prebiotic fibre and phytooestrogens/insoluble fibre, could not be reliably estimated because of the limited number and heterogeneity of the interventions. In addition, three heterogeneous ongoing RCTs were identified, investigating green tea (n=1) and eicosapentaenoic acid (n=1) in colorectal adenoma survivors and dietary modifications (n=1) in CRC survivors in remission.Conclusions:Overall, this systematic review highlights the need for further research, especially in CRC survivors, as we identified no completed and only one ongoing RCT in this population.European Journal of Clinical Nutrition advance online publication, 13 January 2016; doi:10.1038/ejcn.2015.210.

AB - Background/Objectives:Nutrition and dietary supplementation may modulate outcomes in colorectal cancer (CRC) survivors. However, no recent systematic review has focused on randomised controlled trials (RCTs). The aim of this systematic review was to examine the effects of nutritional RCTs in survivors of colorectal adenomas and cancer.Subjects/Methods:Medline, Embase, Scopus, Web of Science and the Cochrane Library were searched to identify research between April 2006 and January 2014. The primary outcomes were colorectal adenoma and cancer recurrence. Each included study was assessed for risk of bias. A meta-analysis using a random-effects model was performed, in which two or more RCTs investigated the same dietary intervention.Results:Eight completed RCTs, all in colorectal adenoma survivors, were identified, with four investigating the effect of folic acid. A meta-analysis of the four folic acid RCTs showed no statistically significant effect of folic acid on colorectal adenoma recurrence (relative risks=0.93; 95% confidence interval: 0.69, 1.25). The impact of the remaining completed RCTs, investigating antioxidant supplementation, green tea extract, prebiotic fibre and phytooestrogens/insoluble fibre, could not be reliably estimated because of the limited number and heterogeneity of the interventions. In addition, three heterogeneous ongoing RCTs were identified, investigating green tea (n=1) and eicosapentaenoic acid (n=1) in colorectal adenoma survivors and dietary modifications (n=1) in CRC survivors in remission.Conclusions:Overall, this systematic review highlights the need for further research, especially in CRC survivors, as we identified no completed and only one ongoing RCT in this population.European Journal of Clinical Nutrition advance online publication, 13 January 2016; doi:10.1038/ejcn.2015.210.

UR - https://www.scopus.com/pages/publications/84954349067

U2 - 10.1038/ejcn.2015.210

DO - 10.1038/ejcn.2015.210

M3 - Article

AN - SCOPUS:84954349067

SN - 0954-3007

JO - European Journal of Clinical Nutrition

JF - European Journal of Clinical Nutrition

ER -