Thus, the objective of this study is to evaluate the usefulness of the pre-treatment SEPTIN9 gene methylation ratio (SEPT9mr) as a predictor of tumor response to TNT and its correlation with tumor size and tumor stage in patients with LARC, since we hypothesize that pre-treatment SEPT9mr should be correlated and could predict tumor response to TNT. This evidence concerns the gene SEPTIN9 and neoplasm.