The association between serum ferritin with colorectal cancer.

There are conflicting reports on the correlation between serum levels of ferritin with colorectal cancer. The purpose of the present study is to clarify the association between serum ferritin with colorectal cancer using a meta-analysis approach. We searched articles indexed in Pubmed published as of July 2015 that met our predefined criteria. Six eligible articles involving 927 subjects were identified. Overall, pooled analysis indicated that subjects with colorectal cancer had lower serum level of ferritin than the healthy controls (SMD=-1.569, 95% CI=[-2.718, -0.420], P= 0.007). Further subgroup analysis found lower serum level of ferritin among patients with colorectal cancer in eastern country (SMD=-1.956, 95% CI=[-3.750, -0.162], P=0.033), but not in western country (SMD=-1.285, 95% CI=[-2.778, 0.207], P=0.091). In conclusion, this meta-analysis supports a significant association between serum ferritin with colorectal cancer. However, the subgroup analysis found that there was significant effect modification of ferritin level by ethnic. Thus this finding needs further confirmation by trans-regional multicenter, long-term observation in a cohort design to obtain better understanding of causal relationships between serum ferrintin levels and colorectal cancer, through measuring ferritin at baseline to investigate whether the highest ferritin category versus lowest is associated with colorectal cancer risk.