A direct comparison of the prognostic effect of gene-expression groups identified based on the “KRT20/top-crypt” two-gene scoring system with that of traditional pathological grading, using multivariate analysis based on the Cox proportional hazards model, was performed on a subset database of 181 microarrays annotated with grading information (Smith database, n=181, see Supplementary Table 1). The analysis indicated that the prognostic effect of “KRT20/top-crypt” gene-expression groups is not confounded by and is associated to higher hazard-ratios (HR) as compared to traditional pathological grade, independently of the gene chosen as marker of the “top-of-the-crypt” CA1+/SLC26A3+ enterocyte-type cell population, with the only exception of CD177 (A, CA1; B, MS4A12; C, CD177; D, SLC26A3; * p-value < 0.05, ** p-value < 0.001).