The variations in the MMP-9 serum levels intrinsic to age and gender described in our family-risk cohort, together with the epidemiological fact that both AA and CRC have a higher prevalence in males and in older-aged groups and hence are factors considered predictive of colorectal neoplasia1, 31, well justify the need of correcting the concentration of this metalloproteinase by these confounders. Here, MMP9 is linked to colorectal carcinoma.